Just short of a masterpiece.
Gameplay: 8
The gameplay really captures the feel of the DBZ games. It basically revolves around melee attacks (square and triangle) and dodging (with X). You can, and should, also use ki attacks (with o) and special Ki attacks (back o and front o). These attacks are usually long range and take up your ki, which you bring up with charging. You can alternatively charge and go into hyper mode, from where you can knock the opponent away and go into a dragon rush mode or use your ultimate attack.
There are lots of options there, but in the end a lot of the fights will seem similar, mainly cause all the characters are almost the same. Their attacks are very similar and predictable.
Graphics: 10
Nothing to complain about here, the game has great graphics for its time, and really captures DBZ well.
Value: 8
There is a lot to do here. You can level your characters up to lvl 99 and upgrade their stats. Dragon Universe tells the story of each of the characters, and in total that will take about 10-15 hours to finish. After that there is the world tournament and dragon arena, which could take another 10 hours. However, there is a chance you will get bored of the game quickly, especially if your not a great DBZ fan.
Tilt: 9
As a DBZ fan I really love this game. The soundtrack is great for a game like this, and the story is told well enough.
Overall an 8.5. More variety in the gameplay would have made this game a masterpiece. But as it is, its a superb game and far better then the Tenkaichi series that comes after this.