The Grandia series deserves to be popular, if only on the strength of its combat system. It is indisputably one of the most challenging, stylish, and downright fun combat engines to ever be found in a JRPG, and it should be more influential than it is.
However, the Grandia games also tend to start strong and bog themselves down in the end; witness Grandia II, for example, which was one disc of pure awesome and one disc of considerably less awesome. The combat system basically yanked it bodily through a storyline that went from interesting to formulaic all at once, like somebody had flipped a switch.
That trend continues with Grandia III, the newest and arguably the best game in the series. The combat system is great, the voice acting's good, and the storyline is... a mixed bag. It uses a considerable dose of humor to liven up a by-the-numbers plot (Grandia II did the same thing, compensating for its equally derivative main storyline by making its hero one of the most bitterly sarcastic bastards in the history of video games), but it's never more than tolerable, and it's actively painful by the time you hit the second disk.
Yuki's a kid with a dream: he wants to fly. He spends his days building airplanes in his garage, rather than becoming a potter like his mother Miranda wants him to. On one of his test flights, things not only go unexpectedly wrong, but he runs into a mysterious girl named Alfina in the middle of the forest.
As it turns out, Alfina's a Communicator, her people's spokeswoman for the gods, and there are people who want her silenced. Yuki and Miranda set out to return Alfina to the mainland, and in so doing, get mixed up in the problems of the larger world outside their island. Yuki wants to be the best pilot in the world, and at the same time, he's walked right into the middle of whatever trouble Alfina's in. Cue epic struggle for the fate of the world.
Grandia III, like the game before it (nobody counts Grandia Xtreme), is linear to a fault. You enter a dungeon, fight your way through it, get some storyline via dialogue sequences, and then you go right back into the dungeons, with an occasional timeout to explore a town or two. Each dungeon or town has an automatic automap in the corner of the screen, so you can't get lost, and it's usually pretty easy to tell where the treasure's hidden. Just look for the dead ends.
Basically, this means everything in Grandia III is focused around getting you to and from the action as fast as possible, and fortunately, it's really good action. The combat engine in Grandia III is, simply, the best combat engine to ever appear in a Japanese RPG, and manipulating it provides pretty much every reason there is to purchase this game.
You begin a combat by running into a monster on the dungeon map; you can stun it first to get the first attack, and if it hits you from behind, it'll get the first round in. Initiative is handled via a circular meter, which keeps things simple even when they get chaotic... and they do.
The combat's sort of real-time, yet not. Characters move around the field of battle at random as they attack and counterattack, with the action freezing every time one of your character's turns come up. More importantly, you can cancel out an enemy action with certain special moves or the Critical attack command, but naturally, this requires your character to have the time and space to reach and attack his target. By the same token, you can avoid attacks by hitting an enemy first, running out their allotted movement before they can reach a character.
The effect of all this is a deep, but surprisingly approachable system that comes about as close to encapsulating the actual feel of a pitched, chaotic melee as it's possible to do.
It also leads to some truly challenging fights. Grandia III feels little compunction about turning up the difficulty at times, to the point where even an ordinary monster encounter can be a handful. You need to break yourself of some old, bad RPG habits, as well as pay close attention to what's going on onscreen, in order to really succeed; you can't just tape down the Attack button and hope for the best. You need to actually use teamwork.
It's a brilliant system, and while you're using it, Grandia III is arguably the best "classic" RPG on the market at the moment. When you're not using it, you'll be wading through a mediocre storyline. It made me want to scream after about three hours, and it kept going for quite a ways beyond that.
Here's the thing. How much you like Grandia III is going to depend largely on how much of a role the storyline plays in how much you enjoy an RPG. This is an impressive package, with expressive graphics, a versatile combat system, decent music, and nicely customizable characters, wrapped around the typically linear Grandia style of gameplay.
The story, however, is cliched, even beyond the usual bounds of Japanese RPG design. Every plot "twist" it has is heavily telegraphed, and vehemently overacted; the voice actors are all pretty good, but all of them deliver their lines like they had too much coffee or something. If you could just skip past the plot as fast as you could and get back to the dungeon-crawling, that'd be one thing, but Grandia III delivers its plot via unskippable cutscenes and interminable dialogue sequences.
Thus, this is a recommendation, but a qualified one. If you're looking for great, satisfying combat, look no further, but be ready and willing to wade through the story.