I find the 12" Radius on my Maruszcyzcks nice and easy, with no big jump when skipping strings which is always when a tighter radius will trip me up. I had a crack on one of Alan Cringean's glorious creations at the Bass Show last year which has a completely flat board, zero radius, and that was ridiculously easy to play. Obviously they're high class kit so other factors may be involved, but it instantly made me feel like a better player... unfortunately the wife didn't believe me! One day though... one day...