I heard good things about it from other battle buddies in the Army. I have no first hand experience with it. But I would take christopheel advice read the section first. Its all about what ya want to do and what supplements to take to help you supplement your diet and excerise.
http://www.animalpak.com/html/article_d ... tion=packs .........I looked this stuff up it may let you know what combo you want to do. I am a big fan of supplements and say great things about them. Hope this helps and happy training.
Animal Pak is a multi-vit, so probably the Mega, is like an enhanced version possibly with extra things, or increased levels of Micronutrients and Carotenoids, or possibly extra anti-oxidants etc etc.
There is almost certainly no traces of Animal in them though. Well none that I know of anyway .