I have shot both a S&W .460 XVR and a S&W .500 Mag. The S&W Model 500 kicks a good bit harder then the .460, but the .460 is noticeably louder. I like the .460 s&w because you can put .454 or .45 long colt in it as well, so it is like 3 guns in one. I can't tell you much else about it, I just fired 5 shots from each at a gun range, nothing major. Both were extremely accurate when cocked first (single action) and then fired.
Oh also the guy who owned both pistols, told me you can get the .460 ammo for almost half the price of the .50 mag ammo.