I think it is all mental. From what I know, all players don't have a big enough sample size from each site played to give accurate results, but it would not surprise me if if all sites were basically even with the amount of variance, bad beats, etc. I have ran into the same situation as you but now I am running better on Carbon than Black Chip. Once I started playing live, I realized online poker is identical other than you see thousands/millions of more hands online. Live poker hands out the nastiest runner runner miracle card river action as online.