A-ma-zing. I've had a ton of fun, everything is spot on: graphics, animation, audio, level design, writing.. it's a real gem. The controls are hard to master but they make sense, so it's not frustrating (at least to me, I guess more casual players might have more difficulty - edit: welp, see below). I loved the paint splashing when killing enemies and the boss battles were great.
The final boss was pretty tough, but with perseverance I managed to beat it :)
Edit: Ah and LOL, I just read some comments and I see there's a Brake feature which I wasn't aware of... Well like jvalen I beat the game without it, but it was hard :P It definitely makes sense to have it though, the game is pretty hardcore otherwise. It would make for a pretty good achievement however for a potential post-jam version to beat the game without braking ;)