An excellent start! Simple yet highly effective chord progression and a good guitar sound. However, if possible, get yourself a keyboardist ; either that, or a lead guitarist with one hell of an effects pedal :D . Your music would have sounded a lot better with some ambient backing, or at least some countermelody - the guitars by themselves sounded a bit disjointed. Try inserting some softer "chorus" gaps between the riff variations as well.

I think you've got something great going here. Keep at it! :cool: