I use Wilson Combats exclusively in my 9mm 1911s so my first hand recommendation is WC... Make sure you don't purchase second hand -- the current gen 2 WC 9mm mags are the ones to have. The gen 1s have some problems. Just an FYI -- WC will swap out any gen 1 9mm WC mags for new gen 2 mags -- at least they did a year or so ago as I sent a few gen 1s in and got back gen 2s within a few days...
One thing -- I only have 9mm 1911s with integrally ramped barrels at this point. I had a Colt 9mm 1911 a few years ago without an integrally ramped barrel and literally couldn't get any of the several brands of mags I tried to work without stoppages. I tried them all -- gen 1 WC mags, Tripp, MecGar, MetalForm and CMC... Not saying they're not good, I just couldn't get them to work -- even with hardball...