I've got a ASAI OnePro that I on occasion will pull out and do some shootin'. Can't get'em any more in Kalifornia, since they'd never pass the drop test with their feather-weight triggers; not to mention they're not imported into the US.
For .45 target shooting, there's the 1911 and then there's everything else. You don't need a $1400 bullseye gun to have a 1911 that's so accurate it'll make your jaw drop.
Get yourself a basic model (I decided on a Kimber Custom Classic when I was in your position) and shoot the heck out of it. Then get a trigger job and a good bushing fitted. Total cost should be a little more than your Sig 220 but it's a heck of a lot more fun.
HK Mark 23 SOCOM with KAC suppressor:
Accurate, reliable and you can plink all day without need for ear protection. It is a pricey system but when it is banned it will be worth a fortune!
Colt 1991A1: straight out of the box with a little dab of color on the front sight. It will also make an excellent base gun for a custom 1911.
Glock 21: If the thick grip doesn't bother you it is a fun .45 to shoot at the range.
Both are reasonably priced, durable, soft shooting for long range sessions, mags are cheap and they're great defense guns should you need to call upon them.
Get a baseline Kimber. They are just as accurate and well-built as the fancier models in their catalog. The price you'll pay depends on the amount of extra fluff you want.