have you handled both guns?
I like them both. But.. there are little things I like about the Ruger over the Smith that breaks the tie for me. For instance: I love Ruger's push button cylinder release way better then Smith's release. I also like Ruger's sights a little better, and like how the fronth sight attaches for easy chang out.
I think S&W comes a bit better finished, overall, from the factory.. but there is the price difference to consider.
For me, Gp100