This game cannot stand against "real" fighting games like the Street Fighter II series...
The fighters play all different, but I think the game is a little imbalanced, since it seemed to me that some fighters had much stronger combos than other ones. This game has a weird password system. I completely dislike it. A fighting game with passwords? This can't be true... And some of the password letters are really difficult to read, so you have to be VERY careful while writing them down, or your progress will be lost forever.
While progressing in the game by beating up your opponents, your character learns more and more combos. At the beginning, you have almost no combos which can be executed. That's a little strange, too... but never mind.
Overall, this game is pretty nice, but it's far far far away from giants like Street Fighter. Maybe it would have been better if it had been balanced a little more and if they hadn't implemented the crappy password system.
There's really no reason for you to buy this game, better get a "real" fighting game instead! If you want to try this weird game, OK, do it, but be careful while writing down those crappy passwords! ;-)