The drums cut through quite nicely, and this piece does have an interesting atmosphere that keeps me intrigued to the point where my mind seeks for meaning. In other words, it gets me wondering what to expect next. Although it does tend to be a bit repetitive, I like the synth and bass. I imagine this to fit quite nicely to a FPS sci-fi kind of game, or any game that involves one to roam around.
The one critique I'll mention is the lack of variation after about 2 minutes and 30 seconds of listening to it directly, but like I said before, if I were to listen indirectly while doing something else, it can be effective.