I have been carrying my sig ultra compact two tone since 2012. Not a very long review. I shoot about a box a month to keep proficient though it's slowed down for a couple moths due to shortages (practice lately with tula steel .45 also). I would guess around 500+ rounds through the pistol. I have had ZERO failures of any kind. This pistol was a CERTIFIED refurbished (red box). I have checked the barrel bushing for any cracks and have seen none.
Only issues are the lint build up and some staining of the stainless barrel from sweating in the summer. I carry in a SUPER WELL MADE S&S IWB holster.
I forget it's there sometimes. I measured it at 2lbs 1oz loaded with Hornady critical defense. For comparison my Sig stainless traditional carry is 2lbs 8oz loaded and my Sig two tone traditional 5" is 2lbs 12oz loaded (one more round though).
I have also had nothing but 100% with my 3 other sig 1911's (scorpion carry tb not pictured) though the compact carry only has about a box through it. My full size two tone cycles in my EDC when clothing dictates I can carry a full size. I'm about 5'7" and 150lbs athletic build and I don't like to wear bulky clothing. The handle is what gives the full size away on me and the barrel blocks my wallet iwb. I got the stainless carry to try though and will rotate that in too.
As for shooting all are great shooters. I normally shoot a steel 8" knock down target at 30yards. I shoot rapid fire and normally run to the the firing line to mimic some stress since I train for CCW. I can hit the 8" target with 75% accuracy with the ultra compact and 100% with the 5". I consider it my lack of skill with shorter sight radius. The 5" has a different rear sight too ( a horizontal tritium bar) vs the ultra's 2 dots.
My long term plans include trying to carry the 5" more and have the ultra compact for summer use. I will say I trust my life with the Sig 1911's and can shoot well with them. I used to carry a glock 26 and just hated it. I love the idea of it but it just did not work for ME. I also tried and did not like a M&P compact. I think the 1911 just fits my hands perfect and shoots like a dream.
I have only one negative about the ultra compact, and that is the slide profile of sig. I love the traditional slides much better and often think of getting rid of it for a Kimber that looks the same. But it works and I got a holster that fits well. I used to not like the looks of the external extractor, but it works well and was also in Browning's original design for the 1911. No issues with that.