Looks great. Music and soundFX are good, but I had very loud footstep sounds, not sure if this is intentional. I can definitely see the potential for a fun shooter, especially in co-op.
I encountered a few bugs. One complete lockup, and another where my mouse pointer locked up in escape menu. Except for the footsteps being too loud, soundFX and music is good. I would have liked the weapon to have a bit more recoil or something, but get a nicer feeling when shooting stuff.