This is another Rhythm game in which you must play your Taiko (Japanese drums). The controls are very simple: You use the directional pad and/or the buttons to play the red beats and the L and R buttons to play the blue beats; new to the series is the bell which you can ring by tilting the analog stick. So you can see that the controls are really simple and you can start playing the game without going through the tutorial.
The game has 4 levels, from very easy (kantan) to demon (oni). In the early levels, the beats are spaced so you can get a grip of the rhythm and some songs really seem very simple. However once you advance to the next level you will find the beats coming more often and requiring you to make a smart use of both of your hands, because it will be more easy to alternate the red beats from the directional stick and the buttons in order to be ready for the next batch of beats. Namco really developed a clever way to use the PSP to replace the traditional "sticks" you use in the other versions of the game.
The original song selection is pretty good. With music from some Namco Games (The Katamari Damacy title is simply awesome) to Classical Music like the Ride of the Valkyries with a decent selection of JPop and original tunes for the game. However the people of Namco was very wise to offer some new songs in their site which you can easily download to your PSP and get even more new tunes to beat .
The graphics are OK for the game, nothing to advanced, but believe me, they get the job done. The characters are very well designed and you will grow fond with some of them, specially the little Taiko.
The only problem with the game is that in the most difficult levels even the easy songs are very hard and I really find impossible to get some combos done. I've really failed a lot of those songs no matter how much I improve my scores in the lower levels. However the fact that you will gain more experience for every song played will be enough to keep you entertained for a long time with this great game.
If you are really into the Rhythm games and don't mind to browse through some Japanese menus, then you should definitely import this game. Also there are a lot of sites from which you can get instructions to download the new songs.