Well I used to use 11's and the bending was never a problem, 12's it started to get a bit hard, - 1 step bends hurt, 1 1/2 step was impossible! And I had to buy a plain G as well as the set.....
I use 10's with a heavy bottom nowadays but I'm a bit surprised that there's not many 8 or 9 users on this forum but then again downtuning has taken over in the metal world now so may be that's why?