Difficult control with WASD -- prefer arrow keys.
The mech was difficult to pilot. It kept sloshing around. Also, splitting the fire between the space bar and the mouse button was annoying. It would be better to have two side-by-side keys, or keep everything on the mouse button.
Targeting was difficult, and the mech kept slewing left-and-right even when those buttons were not being pushed. Was there a sort of recoil or just some random movement?
Not really very enjoyable, though I stuck with it for a few levels to see if anything was interesting.