It was so-so.
Graphics are good. Sound is okay. But what i found lacking was a direct way of regaining health. Those Rocket Flame guys died way too fast for any healing. I still fought my way to level 9, and then got owned by the boss in 10 secs.. This could be a game, it just needs some heavy balancing. For instance, the enemies are too fast and your gun is too slow. For me, faster bullets would solve it, as you can't prevent the enemies from hitting you anyway.
All in all. It was a decent experience. =]