Gundam Seed, a favorite anime/manga series to some and also part of the various Gundam universes, there are some precautions to getting this Japan-exclusive title.
Being available only in Japan, the in-game text would be in Japanese, yet most PSP titles are region-free, which can be played on PSPs available in other locations other than Japan. As an American Gundam fan, I have found it to work fine on the PSP I got in the U.S. A good way to explore the game is to experiment with the few options to establish familiarity with the game modes and settings.
Rengou v.s. Z.A.F.T. was originally released as an arcade and PS2 title in Japan, but was later brought to PSP with some changes:
-Some OMNI and ZAFT pilots and units from the sequel series, Gundam Seed Destiny, are exclusive to play as in the PSP installment. They are already unlocked in the PSP version.
-Mission mode is exclusive, being able to complete a series of missions either as a ZAFT or OMNI pilot, also seeing the perspective of the main storyline with some differences.
The gameplay is unique and eventually can get repetitive after a while, but those in the U.S. who have played Mobile Suit Gundam Seed: Never Ending Tomorrow or Mobile Suit Gundam: Encounters In Space would find gameplay almost similar, or even more better, and toppled with great graphics and animation, as well as using Japanese audio dialog and original music from the anime can make Rengou v.s. Z.A.F.T. a great title for a Gundam Seed-fan.
I would hope this information is helpful to American buyers, as well as others looking into this Japanese Gundam game.