To hear Japanese or to not hear Japanese...
Truly a marvelous celebration of the legacy of Final Fantasy. There's so much to unlock, but it's the reason this game isn't all that tourney-legal. It's like it tries to prevent you from playing this game competitively as much as possible when you have to master a good 100 abilities for about 30+ characters... maybe the game isn't supposed to be played competitively.
It's still mad fun with it's fluid and awesome animations. It's an eternal question of 50 / 50 in combat with free 3D movement. This isn't an execution-heavy game by any means but it's still equally important to know spacing, baits and other fighting game concepts.
Specific to this version is the ability to play the game with Japanese voice-overs with English subtitles. It may be well worth the trouble, the voice acting is awesome in it's own way.
If looking for just Japanese voices, this should be your go-to version for just that. This version has it's own individual save file so I wouldn't bet my money on being able to play against people who have the NA, JPN or EU versions of this game. I've paid enough for this mash-up as it is, but I like my Dissidia 012. I get something out of this.