I picked up a GSG 1911, too.
The mags are better designed than the Rugers (they have an internal feed ramp that keeps the rounds feeding smoothly without jamming into the feedramp like my 22/45 does sometimes).
Easier to disassemble. Feels better in the hand, mags drop free without hesitation and feel like real mags. Accepts an adapter for a suppressor readily.
I'm not getting rid of my 22/45 by any means, and I don't suggest that you do, but I can tell you, that much like my 10/22, the 22/45 is getting mothballed.