I like the idea, I used to have a game like this on DS called Elite Beat Agents, and I loved that game. However, this game I don't like. The music in it isn't great (Just IMO, no offence intended), and the syncing of the notes was off by a long shot. I usually either got too far ahead of myself and got bads, or fell too far behind and missed a bunch. The ring isn't enough of an indicator when to click.
Also, I'm pretty sure the Sharp achievement and medal is broken. I missed a bunch in the first song and still got it.