Underrated = FFV and FFXII

Both are excellent games and tragically underrated. Final Fantasy XIII is a brilliant game with an incredibly interesting, varied, and beautiful game world. It has more end game content than any FF game.

Final Fantasy V is a huge improvement on IV imo. The game is epic, and has an excellent job class system.

Overrated... is Final Fantasy IV. There was serious balancing issues in the game. On the moon for instance, an enemy would hit one of your characters for 200 hp, and then the next turn, hit your character for 1000+ hp and KO your character even though your character had max health. lol FFIV has its charms, but it is overrated imo.