My rock climbing gym does not allow barefoot climbing (I was even offering them to sign a waiver, did not help). So I have been happily using my Vibrams KSOs, so far so good. I have been able to climb whatever up to class 5.9 in them. If I go on a tougher route the foot holds are too small and I need to switch to my real climbing shoes. I do not like them because they squish my feet so as a compromise I rarely go on 5.10 and above.