Really fast and heavy, but the constant speed seems to desensitize me to the heaviness. Breaking it up a little more might have really made each new part stand out. Slow, loud drums (or even bursts) also do the trick. The guitar and drums also sound off sync toward the end.
One thing I will give you mega-props for is the end. Something about it really made me whip my head around and take a look at what part of the song it was. Not sure what it was, but I liked it!