I have never shot one from a bench rest, but most P220s will shoot tighter groups than most production 1911s.
The 5" P220 Stainless Match Elite is one of my favorite P220 production configurations.
This one has had a bit of work and is now chambered in 10MM.
Do not fall into the marketing trap thinking that because the word MATCH is in the product name this firearm is any more accurate than any other production P220. Match is used for the 5" target sighted guns. They have the same fitting, actions and barrels as all other P220s.
You gain a longer sight radius and the adjustable sight (there were a few fixed sight 5" produced)
If you are looking for the 45ACP tack drivers from SIG, you have to look to the P220S. This is the P220 Sport, P220 Sport Stock and P220 X6
The P220S is made in the Mastershop in Germany. These have hand fitted slide, hand honed single action breaks and match barrels. These are a quantum leap above the production guns in terms of accuracy.
SIG does not hand hone the DA break on any of the DA/SA versions.