Nice 3D graphics and good variety of enemies for the duration of the game. The game-play s too simple trough. I finished this on my 4th attempt and although I did buy some upgrades, I feel they were unnecessary and I just won because I adjusted to the game mechanics. I won before buying machine gun and after that I replayed game one more time with machine gun and the result was me winning in a flawless game with no heath lost.
More complex game with let's say three different tracks each more harder then other and different enemies on each of them, a crosshair instead of standard winnows cursor, visible weapon tips, at least one additional weapon and an animated level exit would earn a five stars rating from me.