Dark...I like it.
I definitely agree that this can be used in some kind of shooter. However, the imagery I get is kind of strange.
Do you honestly want to know where I can picture this song being used? Haphestus Core in Rapture (Bioshock). I know it sounds strange placing this song there when the songs made and selected for the game were done in the 50's, 60's, or just have the 50's-60's feel to it, but I think it's just the way the beat goes, as well as the instrument lineup. It sounds like someone wandering through the core of the facility, their hands gripping their guns tightly, tense, nervous, ready to blow away anything that threatens their life.
So, of course, the first thing that popped into my head was Haphestus Core. Awesome song. Keep up the great work.