Decent
Dissidia is a good fighting game. Once you get used to the battle system, which the main story mode helps to teach you fairly effectively, it continues to get deeper and deeper as you play more. There's a lot of customization in the game, and that may appeal to some.
My only problem with the game would have to be the cutscenes. They're awful. Don't get me wrong, they look great, but the writing and acting is absolutely horrendous. Luckily, the developers noticed this and let you skip the cutscenes (even the text ones) by pressing start. This also works to pause the cutscene if you actually want to watch it.
Addictive gameplay + nostalgia factor - bad cutscenes = a grade of B-.
Recommended for fans of both Final Fantasy games and fighting games.
Not recommended for anyone else.

Addictive
This title makes me feel like I am playing through the Final Fantasy 7 Advent Children movie! Great epic battle, great cinematogrophy and you get to play all heros and villains from FF1 to FFX!

Pretty good
Great little game, well worth the money. Many many items to collect, it will keep you entertained for AGES. I love the dual colossuem, and quick fighting modes.

Downsides: cant play over the internet, and story line/dubbing kinda lame. I dislike clouds voice, and the whole "trying to make the game epic sounding" voice even though the storyline is lame. Not sure if it was translated incorrectly, or because its japanese and I didnt get it.

Great for those who are fans of the ff series and aslo the ones who arent
great innovative fighting system keeps players on their toe and always mixing up their styles. lots of bonus content to keep you intrigued for hours on end. definitely worth it!

No title
A truly additive game with unimaginable amounts of content in it. The combat is unique, the action is fast and the face that all of this is crammed into one UMD is truly impressive.