I can play up to 16 indeed. But the bad thing is, that after 6+ i am getting too scattered. You know, it's not much time to act and when you have so many tables opened, it can happen, that you have a good hand a several tables at the same time. So then it can happen.. while you figure how to play AK from early position, you have folded QQ at another one.. Bollocks! That's why i try not let it happen, that i play more than 6-7 tables. I become way too unconcentrated and it's not good for my game.