I don't know what i think of the cast yet, because as Ryo Chan said, most of them seem to have mainly done work on video games.
Though i'm sure Steve Blum will do a good job as Zabuza, and Dave Wittenberg has an extensive cast history and has also played a few characters voices i have really liked (shame i had to see the picture though, i hate seeing voice actor pictures), but we will just have to wait and see if they will actually do a good job as the characters