Oh, this was a while ago. Someone made a Rhythm Heaven/Paradise parody game with an MLP theme. But it was completely unplayable due to the timing being off (although I feel the original game has the same issue).
 
Because you need to press the button on the frame it happens or a certain amount before it happens. This means to make sure you never miss a beat, you should always press before the beat. Ruining the experience. This unlike Guitar Hero / Rock Band where you have the same window before and after the note.

Hey, baby! How’s it going?  
This beat is non-stop!

Tanned, rested and ready!

 
Chae Lim from The King of Fighters Maximum Impact  
_{The second female TKD fighter in the whole franchise}
 
I’m still the ambassador of SNK PLAYMORE to Derpibooru, despite the company being bought by Ledo Millennium (of China)