I agree with Easygoing, I have a 686 that I think is great so I went out and purchased a 22 caliber 617. The only problem is that I haven't got to shoot it yet!Probably no "best", as it's really what you like, but the S&W 617 is gorgeous. Fit and feel nearly identical to the S&W 686 .357 and holds 10 rounds of .22 . All stainless and just beautiful.
I'm biased, as I'm a 686 owner...