My biased choice is the GP100, the perfect handgun, in factory form, for my hands, but, really, either will do. I let my two L-Frames, a 686 and a 581, get away from me, in the Eighties, when I traded them for N-Frames, but, sooner or later, I am probably going to “replace” at least one of them, in my nostalgic seventh decade. I have accumulated several GP100 variants, since buying my first one in the very early Nineties. The original-pattern Ruger GP100 grip is a perfect fit, in my hands., whereas an S&W revolver requires custom or altered grips, to work as well.