FWIW...
I shoot club matches and mainly do it to improve/maintain my CC abilities and have FUN. I've been shooting for several years off/on when its too hot to compete in rifle matches. It's amazing how much I've improved in (action) pistol accuracy. From draw, proper hold, sight picture, trigger control, reloading there's nothing that compares to being put under artificial pressure and performing well. When the buzzer goes off it's all automatic. I can't remember how fast I drew, how quickly I moved, what my hold looked like, etc. - only the holes I put in the cardboard and the procedural rules I broke :-(
Back on subject...
I shoot H+K .45 in SSP class. I use a BLACKHAWK nylon ambi pancake holster (I'm lefty), BIANCHI nylon mag holster. I tend to keep things simple. The more "serious" shooters are using 1911's and GLOCKs but I have big hands and the H+K feels perfect in my hand. Plus the .45 is the only pistol round I reload. Plus, plus the .45 makes the biggest holes!
cheers,
gap