I shot in USPSA Limited 10 division, virtually every weekend from the day the division was instituted until 2010.
I used a five McCormick Power 10 magazines, after trading-in eight of the 10-round "match" magazines.
The match mags didn't work well, at all. The followers collapsed, resulting in feed failures. The Power Mags worked all the time, but they have a peculiar issue with the feedlips spreading. It's not the rolled-in part that positions the cartridge, but the "ears" forward of the lips; they splay out to the extent that the mags won't drop free.
Part of my pre-match ritual was testing them to see if they would drop from slide-down with a round in the mag, and from slidelock with no rounds in the mag. Every weekend, at least one of the mags would fail one of the tests, and I'd have to use a plastic mallet to tap the mags back into parallel shape.
No problems with feeding or lockback.
I shot a bull-barreled longslide pistol for many years, it balanced differently from a 5" bushing-barreled gun but with a fully-loaded 10-rounder in place, the balance may not have been much different.
...its a very special gun and I practice with it a lot ( I have close to 75,000 rds thru it already - and counting )...