Hi Chris,
I have all kinds of alloy frames, 45s, 9s, 380s, you name it. For auto's, I prefer them to steel. I shoot a SW3914 (blue version of the lady smith without the weird frame) and it's just great even after who knows how many rounds and years. Same with my series 70 LW commander, walther P-38 (commercial), colt mustang pocket lite, etc, etc.
They hold up.... Alloy revolvers on the other hand.......
Good Shooting!
Doug