I wore through a pair of Miuras and bought a pair of Testarossas after reading the great reviews. Couldn't find them locally so I went with the same size (42) as the Miuras. They felt like comfy slippers as soon as I put them on, so I returned them for a pair of 41s and 41.5s. I went with the 41.5s and generally wear a US 10 mens street shoe. So far I have only used them on an Entre-prises "natural" wall, and they performed well. I felt like I could smear much better with the Testarossas, and could stick to tiny edges much more easily. The break-in period has been a little painful, but expected. I can definitely tell that there has been some stretch, but I wouldn't expect a lot of stretch overall. Little expensive, but they look and perform better than cheap shoes.