Very good game, DEFINITELY the best in the series, but it's still not amazing.
So here's what it boils down to...Once you learn the controls and become confortable with the way the game plays, that's when you see the game in a much better light. The characters are great, voices are from the series, and the fighting is as close as I can see it getting to the show. It's great that you can actually freely wonder around the fighting plain and that you can destroy pretty much anything in the environment around you. They worked out the whole KI system and melee combat very cleverly I found since there are many different ways to create a combo or to counter/dodge.
I would say that the main bad things about the game is that you can no longer fly around a world map in story mode, instead you just select the next battle that you can choose, listen to a brief cut-scene and fight. Secondly, once you get everything in the game, there's not much replay value to it unless your playing versus mode...but then again, any game of this genre is like that.
Just know that this game is very different from the other Budokai's but it's definitely in a good way although it will take some getting used to. I would also say it's more of a game to buy rather than rent just because it is a long game and your going to want to get all the secrets because a lot of them are interesting.