I recently just started taking M-Stack 3 days ago. So I can't give a very good review of how it works. But from all the reviews I've read on this site along with bodybuilding.com everyone seems to like this product for bulking. I haven't been able to find anything like this product on the market. Animal is a very good company that seems to get excellent reviews on all their products weather it be the Animal Pak or the Animal Pump. I also stack M-Stack with NO Infuse by LG which I got free with the purchase of LG Cold Fusion by the way I would never take again. I tried that stuff for 4 days choking it down everyday and going to the gym and feeling the top of my ears on fire and feeling like I took to much niacin or something. It's not a good feeling to be at the gym and not being comfortable at all. I don't care if Cold Fusion works really good or not I couldn't take the shitty feeling I got from it. But M-Stak like I said has gotten good reviews and the nutrtion partioning seems to be an awesome thing for bulking up and for the price I don't think it could be beat.