I'm having some mixed feelings about this game. While I really do like it and find it addicting when I do get into it, being bad at a single mini game can really drag you out of the whole experience. Because you must beat each rhythm game one at a time, being bad at one game can make life a living hell for a while. It seems like unlocking 5 games at a time would've solved that problem pretty easily.
Score-wise, I'm currently leaning towards an 8. I'd definitely suggest against playing the game on an old Phat, since that's what I'm playing it on and I seem to be having touch screen issues due to poor recognition. Playing on Chessa's DS Lite has yielded some better results, but most people who are still playing on an old DS definitely won't have that option.