I know a guy who is going to use the ephedrine, asprin caffeine stack, (not a supplement containing them, all of them separately). I couldn't give him advice cause I have little knowledge about the stack. A little information about him is that he is not sensitive at all to thermogenics. So don't be afraid to give me an eca dosage that is a little on the higher side. Nothing that will kill him, but something that will raise is core temperature.