Well, if we are talking single actions I have to go with Ruger. Not only does Smith not make single actions, but Rugers are really nice.
Double actions I have to give the nod to Smiths for fit and finish, but I really do love my sp101 over Smiths J frames. I think Rugers are a better match if you are using heavier loads more often.
.327 SP101 3", .327 Blackhawk, S&W 627 V-Comp, S&W 686+ 5", S&W 686+ 3", S&W 581 4", Ruger no.1 .243, TC Contender, Stoeger .410 SxS, some sort of SKS