Great thread with valuable info. All the info is correct about the track pedals with high ridges (cleat and hard sole friendly). They are not very compatible with sneakers with fat waffle soles - I did a 20 mile ride today from Oakland to Walnut Creek and having the waffle soles made it a pain in the ass to flip the pedal and get past the first ridge cause the waffle locked onto it and I couldn't slide in!!!! Second a flexible cork sole was farthest from ergonomically comfortable as the front and rear high ridges bit into the sole and cause two hot-spots when mashing out of saddle up hills! Vans, Nike SB, and the majority of skate type shoes with a stiffer sole and their smooth wavy soles are all good for these pedals though.