Fairly fun game, loved the skill checks on the reloads. Aiming is a little difficult and gets a little in the way of the game, but other than that it's a fun little game.
I personally would either move the aiming to a different set of buttons, like the arrow keys, if I wanted to make everything keyboard centric, or just make it on the mouse. Felt a little bit unnatural to aim and move with WASD at the same time, though I guess it adds a little to the challenge :)