Cannot recommend this more.
Not going to lie,was discouraged from playing because my timings were off.
came back next day, turned on auto-rhytm and played for 5 hours before getting to the end.
with first toon, on easy.

Have since beat on hard for all toons except the last glass cannon, which is instakill.
and am still coming back for more.once you get the gist of it, a full run of the random "campaign" takes about an hour.

the feeling of a rewarding run with good drops cant be put to words
and when things go bad, you are in a new run in seconds, should you wish to.

The red filter gets tiring real fast and might be offputing to some,
but in all honesty is only aggresive in a few map combinations.

Yes, its repetetive, but thats the point, doing it till you master each enemy type, gun and character.

I've yet to do a full run with the auto-rhytm off, but its enjoyable with it on as well,
the game matches your actions to the beat nicely.

Get it on sale, or off sale. great for a quick break from anything and everything.
beware, the music gets stuck in your head for days.