FWIW, I have been told by several people whose opinions I trust, to stay away from 7 and 8 shot variants built on a normal 6 shot model. Apparently (and I do not know this for a fact), the cylinders on the larger capacity models are the same as those on the 6 shot, but with more 'holes' crammed into less space, the chamber walls are a lot thinner, which leads to a decrease in strength.
As I said, I do not know this to be absolutely true, but it would seem likely that less metal = less strength.
I still think you'd be hard pressed to do better than a GP100
My 2 cents