LOVE THESE SHOES!!
let me start by saying i've only just started climbing. as i began to learn about the sport and gear, i decided that quality shoes were the first purchase i would make.
i was a bit puzzled by the varied opinions on how uncomfortably tight climbing shoes should be. i'm an 11 in street shoes and decided to buy the 10.5s based on the fact that they would stretch a bit. they were snug and felt good for several minutes, but got painful not long after that. my toes were just barely curled. i didn't think that i'd be able to last like that for very long in the gym. what convinced me to return them and go for the 11s was actually what was written on the 5.10 box... climbing shoes shouldn't be painfully tight.
the 11s are PERFECT! i LOVE them! they have stretched a little, but nothing that tighter lacing can't overcome... they fit like a glove. i even bought two more pairs for the kids and found the sizing to be true to their street size as well (however, take the time to have your foot measured so you know what your real size is to start).