The polish in this is one is absolutely astounding! It's really something beyond belief, fantastic work guys!
Also I know no one asked for my opinion, and that you'll surely have most of this stuff figured out already since this is only a demo, but still, I'm a whiny brat, I can't contain myself hehe Like several ppl seem to be pointing out, custom button mapping would be really cool, but that's not new to you I assume. Other than that, I felt that when you have to deal with both sides at the same time, the spacing you get on the screen for each side gets slightly shrunken down, giving you less time to react and throwing you off, but once again, that could just be me subconsciously coming up with excuses.
That said, good job, keep at it, and best of luck! :)
Oh, and one more thing, Waiting has some serious Mass of Fermenting Dregs vibe going on. Very nice hahaha