A great button-mashing, RPG for those late hours when you can't get to sleep, but not suitable for everyday play.
The party system is interesting, to say the least. I enjoyed the ability to set the levels of participation of the AI's, and the fact that you could use the touch screen to quickly switch back and forth between members. The only real problem with the p.System, is that it gets slightly annoying having them follow you around....especially when they knock you off into the lava at fire mountain. It often gets to the point where you wish there was a way you could make them stay in one place.
The controls are simple, and easy to manage. A is attack, B is jump, Y is pick up item, and X is cast magic. Although the left trigger+X often glitches for spell stacking. It seems to be a useful feature that never really got the kinks worked out of. It was nice that it wasn't turn-based, as that starts to get old after awhile.
As with most Final Fantasy games, the story is intriguing-it's what makes you continue to play the game. While it's true everyone loves a decent button-masher, with the FF games, it's the story we keep coming back to.
Overall, it's a decent game, and worth playing if you like the Final Fantasy series. The game itself is pretty short, but has online wifi capabilities, so you can exchange friend codes and play with them as well, adding for a decent replay value.
My advice: Don't try and play it from start to finish in one sitting.