I used it once and had great results with it, then i bought another bottle and it didn't seem to work as well (even though my diet and trianing stayed the same) SO I am not sure what was the reason for that. Compared to xenadrine, and those same products on the market, the labels pretty much are the same. As pRECISIOn stated muscle tech is kinda crap so who knows about their manufaturing standards. If it is cheap, try it, but an ECA stack would prbably be cheaper and more effective