The game is very nice! After playing a few times, I wouldn't call it hard. Beautiful art and actually nicely placed (rhythm-wise) arrows—you don't see that in every rhythm game.
It is a little bit hard to see the arrows when they are clustered way too close. And the sound effects are way louder than the music itself. Sometimes you can hear only them and not the music, which is a shame because the music is also lovely.
For such a small period of time and a small team, the game is really good!