I'm not any sort of high speed low drag operator, but I've trained at Thunder Ranch, Gunsite, Sigarms Academy, and with Givens, Farnam and Hoffner as well as local (Houston) trainers. After two courses with Suarez I have to say I learned a lot of stuff I haven't gotten elsewhere and the man makes you think.
Some of what I learned I'll use and some I won't, but Gabe always has a reason for everything he teaches, he's willing to test his ideas against those of his students using Airsoft FOF, and he's incredibly willing to consider ideas from his students rather than just defend his doctrines.
I guess I don't care what his background is as long as I learn something I can use to help me.
I'm signed up for a third Suarex class this fall (Extreme Close Range Gunfighting) and I'm looking forward to it.