Pretty good game, reminds me of 90s free- / shareware games. However, it doesn't really have much personality; enemies, weapons and graphics all feel generic and unmemorable. Gameplay-wise, the enemy hitboxes could be smaller. Currently you die from the tiniest graze (the flamethrower at the start of the lab level is one of the worst offenders). It's better to let the player feel the occasional "oh wow how did I survive that" than "how the hell did that kill me". Also, the enemies are occasionally hard to see. There's a lot of things going on in the game and every now and then I failed to notice an enemy that had spawned behind me. Finally, some technical issues:
-Can't hold a direction when respawning with a continue.
-The fullscreen mode doesn't cover my status bar (Linux, XFCE desktop)
-Encountered a crash at the end of Hell level. I've mailed you the crash log.
So yeah, the game has potential but doesn't stand out. It's something I'd play, but probably not buy at the moment.