I have the S&W 625 and love it. The N frame is a little large for carry, but I'm big enough I could if I chose ... However, I have no reason to switch from my 1911 and J frame back up.
I have not shot the 625 in competition, but I have practiced at home and feel very comfortable with it. It is a real change going to the moon clips from magazines, but after watching JM's dvd I got some tips that made it easier and practice is helping.
If the games you are looking at playing will allow for seven or eight shots in the revolver there are .38's out there that are seven or eight. Same basic feel and recoil, but a shot or two extra between reloads.