Well done, save a few complaints.
1. Ammo. There is never enough of it. throughout the game the player has to spend most of each level breaking containers to find ammo, then running out again seconds later.
2. The player cannot shoot forward and backpedal at the same time.
3. Once the enemies reach the player, massive amounts of health are lost while the player struggles to break free of the huge slowing effect, as well as the fact that the close enemies cannot be hit with most weapons.
Other than that, it is an enjoyable game.