I think I'd sooner by an autoloader in .45 (long) Colt than a revolver in .357 SIG. There are certain cartridges that seem to work well in both autos and revos, like .45 ACP. In addition to Ruger and S&W, several European companies have made 9mm revolvers, including FN for a time and of course Korth.
In answer to KJS, I personally did not think overpenetration is why police moved away from .357 Magnum. I thought it was more about recoil, reload time, and ammo capacity. If I were going into combat with a service handgun (i.e. for some reason I can't have a rifle or shotgun, e.g. I'm a beat cop or a bike cop or whatever), I'd pick a Glock 31 (15 rounds) over a revolver (8 rounds max, and I don't think those were too common when police started leaving revolvers behind). Ditto for small guns, a Glock 33 is nine rounds versus five, max six in a snubby revolver.
I say this is as a dedicated fan of revolvers.
Why cops would pick .357 SIG over 40 S&W? I'm not quite sure, but it may just be that old-timers swear by the .357's stopping power. Hard to argue with, say, a police vet who once brought down some big axe-wielding psycho with a single good torso shot, and he was probably using a .357. I personally don't have any strong beliefs comparing .357 to .357 to .40 to .45, but a lot of folks do.