Pretty cool. It's quite buggy, but, as the name clearly states, this is merely a prototype version. Although the bugs were definitely annoying at times, the game was fun/interesting enough to keep me playing through to the end.
At the risk of stangry PC elitist nerds getting buttmad at me for saying this, I recommend using an Xbox 360 controller to play this game if you have one available (it has built-in 360 controller support). I also recommend that you choose to play at a time when you have nothing important to do or be willing to leave the game running because, if you intend to complete this game, you have no checkpoints or saves or anything. If you quit the game, then you lose any progress that you have made. Even if you do have to quit, though, you won't lose too much time because the game's length certainly falls on the shorter end of the spectrum.
If you enjoyed this, keep an eye out for future updates regarding this game's progress. The developers claim to be listening to feedback from players in order to make a new, full game based on the concepts present in this game. I never heard of this game until I stumbled across it on Steam tonight, but I know that I'll be checking for updates.