DBZ BT 3 is pretty much the same as DBZ BT 2 but with alot more characters. Counting everybodies' transformations, There are exactly 161 characters. It has characters from Dragonball and Dragonball GT. The huge Variety of characters is the best thing about the game.
The battle system is unbelievable. It feels like your actually in the series.
The only bad thing about the game is the storyline....it sucks. Its very short and not very good. The storyline from DBZ BT 2 was long and accurate with extra hypothetical missions as well.
But I still give DBZ BT 3 4 stars just because of the battle system and the amount of characters. It makes up for the crappy storyline.