The 625's are all SS .45's. The standard full-lugs are 4" & 5" in .45ACP, with the latest such offering, the 625JM pictured earlier, another 4" .45 ACP. I have had my 625JM since 2/04, and it has been super. The last .45 Colt offerings were the SS 625 and blued 25 Mountain Guns. A 625MG would make a great 'woods gun' - and is my choice, as I reload. The latest S&W 'Mountain Gun' offering, which was recently still available new, is the .41M blued 57MG.
I believe I would opt for a 4" 629, if I didn't have one. While I owned a 629MG for years, the plus's for the standard 4" made me choose it as a replacement for my 629MG last April. It has a w/o rear and rr front sight, as well as a larger hammer and trigger than the MG. Adding the full size barrel, still partially-lugged, and it weighs but two ounces more. The features make it match my 6" h-l 629, except for barrel length. Add the Hogue .500 Magnum grips, available from S&W Accessories for $35, and you'll have recoil control (Try the same grips, actually stock on new .460's & .500's, for fit.). My local pusher has a LNIB 629MG for $500 in the case now. Many folks buy the 4" 629's, and don't like the recoil... the grip change eases that!
Stainz