Wooow this is made of awesome! An AMAZING boss theme for any type of dramatic game type I can think of. It would work really great in an RPG, in a space shooter or some fast paced platformer. It's epic right from the start and doesn't go down through those 3 minutes it lasts.
My only concern is that when you loop it the ending is way too obvious to the ear. Would you care to make a loopable version...?
Other than that - PEW PEW PEW