I’ve only shot 3 matches thus far, but my patriot vest has served me well. It's light and airy enough to not be uncomfortable in the California heat, and it came in LT sizes which is why I got it over 511/woolrich offerings. the interrior pockets also stiffen the front pannels quite well, making them fold back rather than crumple. http://concealedcarryoutfitters.com/PatriotVest.php
For the gamiest rig though, I did have an idea...
I’ve looked through the rules, but I’m guessing others know them better than i do. Is there a requirement the concealment garment be retained throughout the course of fire? if not, seems you could shave a second or two by adopting a "tactical sarong", i.e. wrapping a shemagh scarf around your gear and clipping it in place. Buzzer sounds, you sweep it away and it falls to the ground leaving your gear unimpeded.
Begs the question though: are you gamer enough to shoot in a dress?