Excellent
gave up at level 16. unbeatable at my accumulated level of twitchiness from the previous ones.
controls could be more predictable. you can't get past the chompers without tapping left-right-left-right quickly in order to move as straight as possible, and it seems that a fraction of a second between taps can make a difference, because you drift off in one direction or the other about half the time.
and that death sound is just, well... mean.
everything else about this game is excellent. very stylish, nice level names, doesn't get repetitive. you keep going because you want to see what comes next. and the absence of a forward button is kind of the point.