Summary: I purchased this game because it seemed very similar to IIDX. The first thing I noticed was the insane learning curve. On beginner mode, up to about level 5 songs are pretty easy. Then level 6 they just go insane.
Summary: I've played the Asian versions of this game and it seems to be pretty similar to the originals, with the enhancements of the most recent "Black Square" edition. If you've played DDR or Guitar Hero, you pretty much know everything about the game play.