I've had a SIG 1911 Target for a few months and just love it. SIG 1911 slides ARE a bit wider than conventinal 1991 slides, but I bought a kydex holseter from SIG and have no problems.
The workmanship is flawless, but the slide does include the Colt Series 80 passive firing pin mechanism, which I had my gunsmith remove, to eliminate a little creep and grittiness, after firing at least 200 rounds, since making any modifications will void SIG's warranty. I am taking this one to my grave.