I owned both the R1s and the SR1911 CMD guns and used both as a base to build presentation guns. I wanted an original name for a WWII gun on the presentation gun for an organization that started in 1944. If you can use a motor tool, a set of jeweler files and a pair of needle nose pliers, plus know what you are doing, you can have the R1s feeding empty brass in about 15 minutes, start to finish. It shoots one inch with Remington Target Master and a half inch at 25 yards with reloads if you are capable.
The Ruger Commander takes a few minutes longer and the one I built required a match sear and barrel bushing plus a spring kit, awful trigger. It shoot about 1 inch at 25.
The reason the R1s is more accurate is the R1s barrel has a dog knot at the end of the barrel that tightens up real nice.
But, the Remington (made in the US) has some weird sights on it and it is not cut for Novak sights, like the Ruger is. Ruger has a cast frame with a CNC cut slide (all US and Ruger).
Ed