holy god! i took 3 RPM and 2 drive from the samples that AN sent me and in about 20 min. i felt like i wanted pick up some one a break them over my head lol, extreme exaggeration, but i felt like i wanted to do alot of lifting, which isnt good due to recovering from an injury, i dont wanna over do it, but ,man i just wanted to say, hell of a supplement, nice clean steady energy and focus along with wanting to rip some ones head off lol A++++++++++ supplement! happy im getting two bottles of RPM!