I have a friend who has had an SDS 625-5 Classic for a long time and has shot it quite a bit. He hasn't had any problem at all. I believe if barrels were routinely popping off of guns it would get a lot more press than this old thread. The truth is that any mechanical item can fail in a variety of ways due to a manufacturer defect or mistreatment.

One thing you do need to be aware of regarding any S&W 45 Colt revolver is that there are multiple power levels of 45 Colt ammunition available (as well as reloading recommendations). Stay away from any load labelled as "Ruger Only". While a load like that probably wouldn't flat out blow up your S&W 625, it is a lot of stress on it mostly due to the thin spot in the cylinder at the bolt notch. Due to the large case size of the 45 it is considered the weak point for the 45 caliber S&W N frame. The 44 is enough smaller cartridge that it allows 44 magnum pressure to be safe in essentially the same gun. The 45 Colt S&W is definitely not weak, but not as strong as a heavily built single action revolver.

BTW, There were only something like 1550 of the 625-5 Classic guns made so it is a bit rare and is highly regarded.