It's definitely very fun. Admittedly, Puzzle Fighter does the same basic concept better, with its large gems, time-locked garbage, character-specific garbage patterns, et cetera. Still, I played it on my Game Gear in total ignorance of Puzzle Fighter, and still had a great time.
That said, the Saturn version mildly disappointed me - I was expecting there to be brief cutscenes before and after every match like the Game Gear version, only to find there really wasn't much of anything between rounds - you just move from round to round. A shame, because I thought the additional dialog in the Game Gear version made the opponents more interesting. Still worth it, since my disappointment probably wouldn't translate over to somebody totally new to the game.
And no, it's absolutely nothing like Puyo Puyo. The similarities end at "you get to battle another person".