I'm somewhat obsessed with 5" revolvers. I have a 5" 686 & a 627. Use to have a 5" 625. And now a 5" 629. I'm casually giving thought to a 5" M60, plus I'd love to cut my 929 off to 5".
Here's the latest acquisition.

A secret of buying used is to watch the on-line sites (Gun Broker, et.al.) and look for the pawn shop gun stores disposing of inventory. This gun probably had a half box put through it before it was stashed away then finally pawned. It came with box and accessories and hardly looked used. $690. Out of state so no sales tax and only a $25 shipping fee. Retail is $800+tax. So I saved about 15%.
It came to me as is from the factory. So the first thing I did was totally strip it. Removed everything, with the exception of the front sight, and the extractor rod lock. Then I sent it to MagnaPort for the standard 2 port treatment.

Marvelous gun. The ports don't help with recoil, what they do is practically eliminate muzzle rise. I'll try to get a video of it soon.
I had never so totally stripped a revolver and I did have to refer to youtube to figure out how to put the stupid lock back together. And then I had to go digging around the other forums for the explanation of the Endurance Package's bolt lock. This isn't shown in any S&W gun smithing book. Easy enough to figure what it was and how to put it back, but the lack of documentation after 30 years is a puzzle.
So, like me, who've never noticed the difference between the 629 (and the X frame guns) and all the other S&Ws, here's picture of the extra little part.

What was happening was the gun was recoiling so fast the bolt was not keeping up and the cylinder would unlock. So this little part, operated by the hand pivot pin, keeps the bolt locked back during recoil.