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Salomon S/Lab Phantasm 2: Can Their First Super Shoe Hit the Mark?
By Matthew Klein

Salomon has made several attempts over the last couple years to get into the road running scene. The majority of their shoes have been a little behind, firmer and not the most exciting, an incredible contrast to their excellent trail line. Their first racing shoe, the S/Lab Phantasm, was shockingly behind as it was more in line with the minimal racers a decade ago rather than featuring the super foams and plates of current day performers. The S/Lab Phantasm CF was much better but again fell short due to lacking a super foam and a carbon plate (they used a composite fiber). Finally, Salomon decided to launch a true super shoe with the early and brief release of the S/Lab Phantasm 2. Featuring a PEBAX midsole, a full-length carbon fiber plate, a maximal stack height and the rare higher drop, Salomon finally has a true super shoe. Before you get excited, there are a few things that need to be discussed in regards to whether this shoe will FIT your needs.

Salomon S/Lab Phantasm 2
Price: $275 at Salomon
Weight: 7.7 oz, 219 g (Unisex Sizing Men's size 9/Women's Size 10)
Stack Height: 37.5 mm / 28.5 mm
Drop: 9mm
Classification: Super Plated Racing Shoe


The Salomon S/Lab Phantasm 2 is a super racing shoe for those who want a long-fitting, extremely neutral riding, bouncy and fast shoe for workouts and racing. The upper fits a half-size long, creating a challenge to get an optimal fit but creating an optimal situation for those who experience foot swelling over longer distances. The new PEBAX-based midsole provides a ton of bounce that responds more the faster you go. A narrow heel/midfoot makes for an extremely neutral ride, best for those without stability needs. While an incredible midsole brings Salomon into the super shoe game, the upper needs some adjusting which I'll dive into in this review.

: On Cloudboom Echo 3


The Salomon S/Lab Phantasm 2 fits me a half-size long. For shorter to moderate-distance races and workouts, I would highly suggest going a half-size down. For marathon and longer distances where swelling may come into play, going true to size may be possible. Having a shoe that was a half size became a bit annoying, so I used one of my adhesive arch felt pads to fill in the rearfoot.

This made the shoe more true to size. Without the pad, the forefoot obviously felt long and there was a fairly normal amount of room with slightly lower volume. With the pad, the toe guard pressed down on top of my toes, the width was slightly snug and the volume was quite low. The thin mesh material does lock the foot in well when the shoe is true to size but it has more of a racing (snug) fit). When it was not true to size (no pads) my feet did slide in the shoe, especially on turns. The midfoot has fit fine regardless of sizing modification. The tongue is thin and gusseted, fitting slightly snug regardless of size. I did not have to tie the laces that tight to secure midfoot, although to keep my foot from sliding forward without the pads I did get some lace bite at the top of my ankle (this was not an issue with the pads).

The heel in this shoe fits fairly normally with a flexible heel counter. There is a top layer of heel collar cushioning that wraps the heel fairly comfortably. Those who do not like stiff heel counters will do extremely well in this shoe as I did not notice the counter at all. However, without the pad to reduce space, it was not the most secure until I really tightened up the laces (which caused some lace bite). This further adds to the upper security being a little iffy thanks to how relatively flexible it is and the fact there is a little extra room fitting long. With the pads, this created a snug fit in both the heel and forefoot, which lended to the upper feeling more secure. The materials, though, are still flexible and do not have much in the way of reinforcement.

Therefore, those interested in this shoe should consider it only for workouts and races where you are going in a fairly straight line on even terrain. Because of the mild sliding, I would encourage the use of socks, particularly thick socks if you are going true to size. If you go down a half size, you may be able to do shorter efforts without socks, but the pressure on the top of your toes from the toe guard may warrant the use of at least thin socks. Overall, the upper fits extremely long and while it has potential, has caused me enough problems that I had to modify it to get a better fit.


The Salomon S/Lab Phantasm 2 is a high stack, carbon-plated, super foamed shoe for workouts and racing. The midsole FINALLY features two layers of full-length PEBAX-based foam called "Energy Foam +" that feels incredibly bouncy when the pace picks up. At slower paces, the foam feels oddly controlled and a little firmer than other super foams, making it easy to warm up and cool down in. When the pace picks up, the resiliency and bounce of the foam become immediately apparent as it quickly throws you forward. The bounce does feel a little slow at first, which matches my longer stride and lower cadence. Running faster track intervals was a little difficult until I found my rhythm, whereas tempo runs and moderate to longer race efforts felt better. The weight is fairly normal for a distance racing shoe. However, when the pace picks up the weight seems to disappear.

There is a 9mm heel drop listed but that is not how this shoe feels. The foam compresses enough that it feels more in the 6-7mm range. The combination of foam compression and the heel bevel make for a smooth heel transition. The width of the sole is narrow, which does make it fairly neutral and not stable for those that need stability like me. The midfoot transitions fairly well outside of being narrow (I fall off the medial side). The forefoot is where the carbon plate is most noticeable. This shoe fits a half size small, which initially made me hit the plate early. This makes for a stiff forefoot transition that feels better at faster paces and a little awkward at slower paces. When I added the foam pieces in the heel to correct the half-long fit, the forefoot was much smoother. The snappiness of the plate only became apparent when I pick the pace up and otherwise provide a smooth transition forward.

The foam and plate combination, if you have the correct size, create a duel personality. At easy paces, the S/Lab Phantasm is fairly smooth and forgiving. The foam doesn't feel crazy bouncy, instead feeling a little firmer (compared to others) and controlled. When the pace picks up, that is really where the shoe shines. I have used this shoe for fartleks, tempo runs, hill repeats, track intervals and raced a dirt XC-Style mile against my students (5:17). Running fast is where this shoe does best and comes alive more the faster you push it. If you can handle the heel instability, it actually does quite well at uptempo paces and tempo efforts, making it a solid option also for longer races if you can get the fit dialed in. The slightly higher weight and slower, albeit big bounce make it feel like it should do better over longer distances than shorter, but your experience may vary with the sizing and heel instability. Traction and durability-wise I would keep this shoe on solid surfaces. It has held up fine. I have used this shoe on both dirt and road and after 25 miles there is only a little wear on the outsole despite my running mechanics. I expect a fairly normal to slightly higher number of miles out of these for a super shoe.


The Salomon S/Lab Phantasm 2 is a neutral racing shoe with no true methods of stability. There are some small sidewalls in the midfoot. However, these are not enough to offset the fairly narrow width of the heel and midfoot. The heel is especially unstable with the narrow platform and soft foam. This transitions into an even more narrow midfoot with the same instability thanks to the width and soft foam. The forefoot is better thanks to a decent amount of unique sole flare on the medial and lateral sides. Combined with a fairly decent forefoot rocker, the transition off the front of the shoe is much quicker. At least, it was once I adjusted the length. When the shoe was too long, the additional forefoot stiffness actually made me collapse more trying to get over the front. Overall, this shoe will work best for those with stable mechanics who do not need stability or do not do well with it in the heel and midfoot. 

Thoughts as a DPT: The Importance of Length in Carbon-Plated Shoes
By Matthew Klein

A frequent question we have received recently is how to figure out the sizing for super shoes. Typically, going with your normal size should USUALLY be okay, but with the different shapes of the plates, this has become more variable. The current evidence on plates suggests that they are only beneficial if the axis of the forward curve of the plate lines up with the mechanics of the toe joints (usually the 1st metatarsophalangeal joint) (Agresta et al., 2022). There are likely additional factors, including muscle and joint stiffness that may cause each person to uniquely react to different levels of stiffness in shoes (McLeod et al., 2020). 

What I was taught long ago when working in running retail is that a shoe should have a half to full thumb widths between your longest toe and the end of the shoe. This was supposed to allow enough room for your toes while also adjusting for normal swelling that can occur during the run or during the day that can cause normal differences in foot size (in addition to preventing toe nail damage). That is still a good RULE OF THUMB (I'm not sorry for that), but that may not make up for variations in how each company curves their plate. Unfortunately, there is no way to currently measure where the curve of the plate in a shoe is unless you can either see it or cut the shoe open. If you can see where the curve is, optimally you may want your toe joints (where they bend), particularly your big toe joint, to be in the center or relatively close to the center of that curve. 

The non-complicated and more accurate way to do this is to put the shoe on and feel how the forefoot transitions. We already know the shoe feels to a runner can be more predictive of success than biomechanics (Bishop et al., 2020). So putting the shoe on is the best way to determine how it will feel. If the forefoot feels weirdly stiff and awkward, the mechanics of the plate may not be lining up with your feet. Please remember that your feet and their interaction with the shoe will change as your pace changes, so if you want to accurately determine whether a plated shoe is appropriate for you, you need to run at the pace (or paces) you plan to use the shoe for. At your goal speed, the front of the shoe should feel smooth and transition forward easily. If it feels like you are climbing over the front of the shoe or it feels too stiff, that can actually make your calf and ankle muscles work unnecessarily harder, reducing efficiency and increasing stress on a variety of structures (including your Achilles tendon and calf muscles). 

In conclusion, finding an optimal fit should be a combination of biomechanical and self-assessed measures. Given the variability of knowing where the curve in the plate of a shoe is, although trying to line your major toe joints up with that is helpful, your best bet is to make sure your toes have enough length at the end of the shoe AND by making sure the front feels comfortable and transitions smoothly. Once you get through that, don't make it any more complicated and go run. 


Agresta, C., Giacomazzi, C., Harrast, M., & Zendler, J. (2022). Running injury paradigms and their influence on footwear design features and runner assessment methods: a focused review to advance evidence-based practice for running medicine clinicians. Frontiers in Sports and Active Living4, 74.

Bishop, C., Buckley, J. D., Esterman, A. E., & Arnold, J. B. (2020). The running shoe comfort assessment tool (RUN-CAT): Development and evaluation of a new multi-item assessment tool for evaluating the comfort of running footwear. Journal of Sports Sciences38(18), 2100-2107.

McLeod, A. R., Bruening, D., Johnson, A. W., Ward, J., & Hunter, I. (2020). Improving running economy through altered shoe bending stiffness across speeds. Footwear Science12(2), 79-89.


Matt: I have a love/hate relationship with the Salomon S/Lab Phantasm 2. I love the midsole bounce that seems to respond and respond to your speed. I hate the weird upper fit and how unstable the heel is. These last two issues have greatly limited my use of the shoe and will likely stop me from confidently using it in races, particularly 10k and over. My posterior tibialis muscle is always extremely sore after using this shoe (and right now it isn't in any other shoe) and I can see how much my ankles collapse medially in this shoe upon landing. The upper fit ruins this shoe the long fit prevents an optimal interaction with the plate and the front feels sloppy. The fit is completely different than any Salomon shoe I have tried before, which have all been fairly consistent/true to size (if sometimes a little short). This something I would expect to be dialed in, especially at $275. If the fit can be adjusted then perhaps this shoe might be a little closer to that mark, but I also believe the shoe needs to be more aligned price-wise with its peers which sit closer to the $225-250 range.

The heel and midfoot instability are also a major limiting factor. I understand this was done to keep weight down, but the S/Lab Phantasm isn't even close to other super shoes that are either at or below 7 oz. I would suggest for stability and weight maintenance, Salomon should experiment with some different rearfoot and midfoot geometries to widen the sole and potentially expand the central gap to act like a guidance line while keeping weight low (similar to the New Balance FuelCell Elite v3).


Matt: The Salomon S/Lab Phantasm 2 is for those who want a super racing shoe for moderate to faster efforts over longer distances with extremely neutral mechanics, lower volume feet and the flexibility to try a few sizes or who are between sizes. The fit is a half size long, which may be great for some people who struggle with being between sizes or who want a little more length in their super shoe for foot swelling. The midsole foam is awesome with a controlled ride at slower paces and a firmer but high bounce with fast speeds. The heel and midfoot are fairly unstable due to the narrow width, making this shoe best for those without any stability needs.

The specs of this shoe reminded me a great deal of the On Cloudboom Echo 3. The slightly long fit of the Echo 3 was something I was able to get over, whereas the S/Lab Phantasm 2 was more noticeable. The foams are also the first PEBAX attempts from both companies, with the Echo 3 being firmer and the S/Lab Phantasm 2 having more bounce at higher speeds. Both also have astronomical prices that are probably beyond what they are actually worth, especially given the fit issues.

The S/Lab Phantasm 2 is a welcome upgrade from Salomon as they finally enter the true super shoe game. However, the price tag is too high, particularly with the issues around fit. The current price range is far closer to something like the Alphafly and Endorphin Elite, which sit a level or two above the S/Lab Phantasm 2 in technology. There is a lot of good potential long-term here, but to compete with its peers (Vaporfly, Endorphin Pro 3, Adios Pro 3, etc) it needs to both adjust in fit and fall much closer in-line price-wise to the $225-250 range that its peers currently exist in.


Fit: (Half size long with slippage. Consider a half size down or extremely thick socks)
A (Firmer but bouncy foam that responds well to a variety of paces especially going fast)
Stability: C [Neutral] (Unstable Heel/Midfoot. Best for those with stable mechanics)
DPT/Footwear Science: B- (Points for finally using super shoe materials, but long fit will cause 1st MTP joint to not line up properly with plate curve. Unstable heel and midfoot not optimal in a higher stack, softer shoe over long distances)
Personal: B- (I really love the foam in the shoe but the upper and instability ruin it for me. Fixing the fit with the foam adhesive helps, but then the upper is extremely low. An improvement but there is still work that needs to be done to fix the above issues)
Overall: B- 


Salomon S/Lab Phantasm 2
Price: $275 at Salomon

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Editor's Note: As always, the views presented on this website belong to myself or the selected few who contribute to these posts. This website should not and does not serve as a replacement for seeking medical care. If you are currently injured or concerned about an injury, please see your local running physical therapist. If you are in the Los Angeles, Santa Barbara, Danbury and Stevens Point areas, we am currently taking clients for running evaluations.

***Disclaimer: These shoes were gifted to me by my spouse utilizing a discount. We systematically put each type of shoe through certain runs prior to review. For trainers and performance trainers, we take them on daily runs, workouts, recovery runs and a long run prior to review (often accumulating anywhere from 20-50 miles in the process). For racing flats we ensure that we have completed intervals, a tempo or steady state run as well as a warm-up and cool down in each pair prior to review. This systematic process is to ensure that we have experience with each shoe in a large variety of conditions to provide expansive and thorough reviews for the public and for companies. Our views are based on our extensive history in the footwear industry and years testing and developing footwear. If you are a footwear rep looking for footwear reviews or consultations on development, we are currently looking to partner with companies to assist, discuss and promote footwear models. Partnership will not affect the honesty of our reviews.

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