All in all, a pretty good game
I'm going to have to agree with some of the other reviews and say that there needs to be a way to earn credits, especially since you only get 4000 to start with (one repair, even just ten credits, takes away one of the chances to buy a new vehicle).
A chance to earn credits would make the fact that flipping the vehicle kills you a little less irritating.
The only other thing that could use a slight improvement is the sound effects. The eerie background sound is cool, but the vehicle could use a few sound effects for when it crashes or something.
Other than that, the controls were cool, and the visual layout is awesome.
All in all, a pretty good game.