Welcome to the forums.
I actually hacked my Wii for the sake of playing this game. I think it's a great game, though a bit repetitive. The graphics make you feel like you are playing in a painting and the controls are smooth. There's just something about fighting 20 ninjas at once that just doesn't lose it's appeal.
I have completed the game with both characters and just an fyi, there's 5 endings. When you beat either characters story line, you will get a new blade. If you then beat both characters final zone with these two blades equipped when you walk through the gate to the last boss, the boss fight will be different and lead to a different ending. The final ending involves you getting all 108 blades and then beating the end zone again (this is what I have left to do so I don't know the specifics).
Still, it feels like castlevania with ninjas, swords, crazy special attacks, etc.
PS: After you beat the game, go into IZU when you get the ability to unlock white barriers and go to the tree stump (special zone). It's called "Total Pandemonium." I highly recommend trying it around level 60-65. It's crazy.