As mentioned above, you should really shoot that pistol before carrying it. I actually own a C3 and it has been a great shooter. I've carried it for CCW and as a range gun. As with most new Sigs, the first couple rounds are usually a little snappier than the rest. your setting the springs and all the moving parts. Luckily, my C3 has been completely reliable. However, I have had a couple 1911's which were not fully reliable from the beginning. Even the "big name" pistols can have their flaws. I had one Kimber that would not feed properly. Turned out to be the magazine. I had one Ed Brown which would not eject properly. Had to send that one back. Had one Nighthawk that would fail to fully seat in battery. Sent that one back to. So, basically, you should really shoot it before carrying. Also, highly recommend switching magazines to Wilson or Chip McCormicks.
As for holsters, if the holster is kydex and designed for a standard 1911 slide, this pistol will not fit properly and maybe not even at all. With leather holsters however, it should fit just fine.