I've been buying S&Ws the past couple of years. For some reason I became obsessed with them after my Dad passed away in February of 2010.
My first purchase was a 25-13 Classic .45 Colt, Nickel, 6.5" barrel. I had been interested in the .45 colt and owned a Taurus six gun, Ruger blackhawk and Rossi 20" 1892 rifle. After buying the gun I started reading about all the new junk and how awful new S&Ws were. I like to tinker. I put a new Wolff spring kit in my 25. The chamber throats are in spec. I routinely hit what I'm shooting at at 50 yards offhand. I own a Les Baer PII with the 1.5" guarantee and an Ed Brown Executive Target. I shoot the 25 as well. My lock has never engaged.
I've bought a new 4" 617. Wolff kit really helped the DA trigger. I put a Burris Fastfire red dot on it. Amazing gun.
I bought a 625 JM used. For some reason I'm not shooting it as well as I'd like.
Used 620 that I've left alone. Very nice, accurate and reliable. I shoot mostly .38 Specials at the range.
I've put Ahrends retro combat grips on these. They shoot often. The 617 goes to the range every trip. I was shooting clay birds off the hill at the back of the bay with it yesterday at 30-40 yards. I don't hit with every shot, but I bust up all the big pieces.
Used 638 with the CT laser grips. Pocket gun, very accurate. No fun to shoot at the range.
I also like the older guns. From a value for dollars there are good buys. I have bought a few older guns in the last couple years as well. My most recent purchase is a K38 Masterpiece from 1948. Shot 100 rounds through it after picking it up at the club yesterday.