Well the K-frame magnums were built around the 158 grain load and when the hot 125s and 110s came into fashion some developed problems in the forcing cone. Now many shooters will tell you they haven't had any problems with their K-frames, but it is a potential problem. Some revolvers have gone thousands of rounds with no harm while others have sustained damage after only a few hundred rounds. Neither Colt, Ruger, or Dan Wesson had this problem, but their frames were larger in the crane/yoke area. That was the reason for the creation of the L-frame. While this problem may never show up in your revolver if the forcing cone was to crack then there could be a problem finding a replacement barrel.
As to your M625 heating up, do you shoot this revolver faster than your others? Moonclips do make for fast reloads and continuous shooting sessions giving the revolver less time to cool down.
Your loads could be using a dirty powder. If cast bullets are used then you can also add in the lead and lube. I've always been a big fan of Unique powder and soft lubes so you can imagine the mess I'm left with after shooting.