I have had these shoes for three years now and put about 7500 miles a year on them. As with most Sidis, they use a European last and run a little narrow. I had hot spots on my normal width American feet for the first few weeks. Unlike Sidis of old, the upper on these shoes stretched out and now they fit like a glove. The carbon soles are very stiff and mate with the Speedplay system perfectly. You can also buy replacement heel tabs when the original ones wear out. The only issue I have had is with the toothed strap that counteracts the upper boa tightener. When the shoes were new, the straps struck the crank arm when pedaling and created a crack in the slotted receiver for the strap. So I superglued the crack and cut off the excess strap. Now, three years later, the teeth on the straps are slipping free, causing the upper strap to loosen while riding. Luckily Sidi makes replacement straps and Boas, but it will not be cheap to replace.