You just get stuck with an unknown amount of the stuff that can actually help, the "proprietary blend". I make iced green tea (no sugar) and mix in L-arginine/AKG, glutamine and BCAA's 1/2 hour before my workout. It's a hell of a lot cheaper, no garbage, and you actually know you're gettin the right stuff at the right dose. I might get knocked for this, but I find it works well for me. Just some food for thought.