Size 43 dangling from the heel. Exchanged for 42. Felt like a glove at first, but prolonged wear is annoying. I think the problem is with the upper which seems to have little stretch. Perhaps the lacquered rubber bands that wrap around the forefoot add to the sense of restraint. In comparison, the KSO material is softer and more flexible, like a blend of cotton and spandex. The ELx material feels rougher and less stretchy. Initially attracted by the thin soles (compared to most VFF offerings) and unrestricted toe movement (thanks to the rubber on the toes NOT wrapping the sides), I really wanted to love these shoes. The upper feels too limited and cheap.