I've played the game to completion, spent over 70 hours with it, even got the platinum trophy. Since everytime I say it was a decent game, I get attacked because apparently I know nothing, I'll say that the game was decent for me (or else I wouldn't have spent over 70 hours on it). The story is good, although the ending doesn't give it a closure (I didn't mind it, myself). The gameplay is good as well, since it builds a decent DRPG with a nice new Mind tactic (your character controls a Mind during battle, and you control both at the same time). The soundtrack is pretty good, even though later in the game, they repeat the dungeon themes (once or twice). There are a decent amount of enemies, although later in the game Euterpe just pallet-swaps, and the bosses can get pretty challenging.
It's still a lesser game compared to Demon Gaze, but even still, it was a nice game for me. I very much doubt anyone that says it's garbage got past the first three dungeons, or even has played the game.