MX Race Last –Featuring a slightly narrower toebox & tighter heel than the Competition last and less overall volume than the Sport last. Designed for a slimmer fit & most suitable for racing.
I bought the 46.5 wide, and they fit comfortably. The fit is good, the race cut makes little up-down wiggle room for the toes, and despite their "race day" moniker, I can use them for long training rides. I also like the low profile Boas a lot. They have traded the mechanism for loosening via rotation for a pull-out-to-release-completely mechanism, so in order to loosen your shoe a bit, you have to pull the boa out, then tighten it rather than just rotate it in the opposite direction. Its nice because the lower profile is less prone to hitting obstacles; I can see it being annoying if you tend to adjust your shoe tightness often.
I have not used the heat-moldable heel cup, i find it provides a snug enough fit as it came.
The sole is stiff, but not too stiff - it provides a solid base for power application but it doesn't feel like a unflexing board like some high end carbon soled road shoes, which makes it more comfortable to run in.
However, I've had durability issues with the glue on the outsole. The lugs, after a few months of use started to become unstuck. The uppers also showed wear. I believe the wear on the toe and uppers is normal - this is a cyclocross shoe with a softer leather toe, not a MTB shoe with a protected toe. The falling lug syndrome, less so. I've had to reglue them.
My biggest complaint, however, is a more substantial one about quality control. The slots in the outsole in which the pedal cleat plate slides is completely unevenly cut between the shoes - the left one is more forward and rotated by a significant (>1cm) amount relative to the right one. It does not allow for even cleat positioning. It caused difficulty in positioning the cleats without extra hardware to align the cleats.
This, and the durability, amounts to unacceptable for the price of these premium shoes and makes me hesitate to recommend them.