I have 3 Sig 1911's and one S&W. They're all great shooters, all reliable and accurate. I prefer the Sigs though, they're just a bit tighter and feel more substantial in hand. I can squeeze a bit more accuracy out of my Sig 5" target, but that's likely because the sights are better than on the S&W 5". I also like the looks of the Sig slide, I have plenty of 'traditional' looking 1911's ... it's nice to have something just a bit different. I completely strip almost every gun I own purely out of curiosity, and certainly every 1911 since it's so easy. I have to say the guts of the Sigs are impressive, high quality pieces used throughout and fit well. The only problem I've had was a tight throat on one of the Sigs that wouldn't chamber reloads ... then I realized my Lee FCD was putting a burr on the crimp. Polished the inside of my FCD, now reloads chamber fine in the tight throat.
I wish companies would stop using S80 firing pin safety setups on 5" guns though. If they want to use that system, why not only use it on guns that are intended for carry?