I love bullethell, and the onbeat mechanic sets an interesting premise for when to dodge and attack.
The gameplay is stifled by some strange hitboxes, the visuals and hitting enemies do not always overlap, which makes it often feel unfair when I die. This is made worse by "on beat" mechanics, which by definition suffer from lag between audio and video depending on the users set up (check how much calibration Cadence of Hyrule has to do).
My hiscore was a bit more than 2450. that's the last score I saw before I died and was put back in the home screen.
Ohw and I love the pun of the title, actually made me giggle..