I currently have about 800 km (500 miles) on a first pair of the S Lab Sonic including use in buffed mountain trail single track, mountain double track, rocky technical mountain trail, across rivers, scree, snowfields, and high ridges, very limited paved road, and in one mountain trail 60 km race. I am putting up this final update now because these shoes are in a rotation with a couple of pair of S Lab X-Series and I will not likely take them to true end of life (EOL) until the end of the summer. I am still using a pair of X-Series that have over 1800 km (1100 miles) on them and they are still performing well in shorter (10 km or less) runs and as a hiking shoe. I expect the same, with one exception noted below, to be true for the S Lab Sonic.
Given that the S Lab Sonic is a very slightly modified version of the S Lab X-Series (reviewed here, here, and here), it is no surprise that it performs similarly- meaning that this shoe is an excellent and durable performer in the mountains. Having logged very limited road miles (<80 km (50 miles)), I will not make any comments on road performance.
I will, however, comment on the use of traditional laces and the removal of the “lace pocket” on the S Lab Sonic- the bottom line is that this is a mistake and Salomon should at least provide for the option of speed laces. The speed lace/lace pocket technology is a superior solution to securing and fitting a trail running shoe for a whole host of reasons that I do not need to enumerate here as they are patently obvious. I am hopeful that Salomon will move on from this “experiment” and return to the 21st century, at least with the S lab shoes. So, ignoring the issues associated with the traditional laces on the S Lab Sonic, what follows is the rest of the final update.
One of the primary changes from the S Lab X-Series to the S Lab Sonic is a a switch from a lycra-like upper material to a very light mesh material. With over 1800 km (1100 miles) on a pair of S Lab X-Series, I have yet to wear out an upper. Not so with the S Lab Sonic- the medial upper area near the flex point is beginning to wear through at this point. This type of mesh upper is well known to accumulate abrasive dirt within the the mesh and lead to excessive wear out (as has been reported on the S Lab Wings in particular). I have been told by other athletes that they have worn out this area on the S Lab Sonic in as little as 400 km (250 miles). Obviously I have gotten better wear than that but this area is likely to begin to fail within the next 150 km (100 miles).
The lateral area of the upper at the flex axis is still intact and does not show significant wear.
I am just starting to see the heel counter wear that was typical in the X-Series. This wear ends up not affecting performance as I continue to wear a pair where this area is worn down through the underlying cushioning material and I have experienced no discomfort or “hot spots”.
At this point (800 km (500 miles)), the midsole is still performing to expectation and I have not noticed any substantial reduction in cushioning. I have noted an increasing frequency of sharp rock awareness that seemed to not be present at the outset. I expect that there is enough EVA compression that some of the sharper rocks are now having a greater impact on the bottom of my foot.
Wear, as in the X-Series, is outstanding. I have yet to wear out one of these X-Series/Sonic outsoles even after over 1800 km (1100 miles).
Again, as with the very similar X-Series, the comfort of this shoe is excellent and is not noticeably deteriorating. This shoe continues as the most comfortable trail running shoe I have ever worn. One advantage to the S Lab Sonic over the S Lab X-Series is that the Sonic runs noticeably cooler due to the lightweight mesh upper. The lycra-like mesh utilized in the X-Series, although not hot, ran warmer- a good thing in cold weather but not a good thing in hot conditions. With the cooler performance comes the potential upper wear-out in high strain areas; as usual all things involve compromise.
Although these shoes are not at EOL, a value calculation yields a current per mile cost of about $0.36US. The X-Series came in at about $0.21US/mile. The question will be exactly when will the mesh upper give out to the pint where too much debris is getting into the shoe and causing issues. I expect that, based on the observed wear to date, I will likely get another 250-350 km before upper wear-out. That would give a per mile cost of about $0.25US/mile, a bit higher use cost than the X-Series. Of course some users have reported that the S Lab Sonic upper is wearing out in as little as 400 km (250 miles) which gives an unacceptable use cost of about $0.68US/mile. Obviously use varies and the user also plays a role. For my use, stride style, and size the S Lab Sonic represents a good value, particularly for a racing quality shoe.
Salomon have managed to not screw up the excellent X-Series product from 2015 and have retained a high performance, light-weight trail shoe that provides a high level of long run comfort, superior trail feel, high durability, and all-around performance on mountain terrain. Highly recommended, but be aware of possible upper mesh wear-out issues.
I will be using the S Lab Sonic in rotation with S Lab X-Series exclusively for training and racing this season including an number of mountain trail 50km-60 km races as well as some possible longer races in the fall.
Based on some information trickling out of Europe and State Side, it seems Salomon will have a new program to offer for 2017. I will put up a “rumor post” on this subject soon.