The only part that's really worthwhile is the dialogue, and even then only if you're already a fan of the characters and enjoyed, say, Sonic Battle's writing or the recent comics. The gameplay is repetitive and poorly balanced, the plot ripped off from some of the dumber comic storylines, and the music nearly qualifies as a war crime.
It's ok, there's just some serious design flaws that keep it from being "good". Things like touch screen controls that you have to use constantly over and over again every single battle because the game is balanced around you using your special attacks every single round and having Cream in the party to restore everyone's MP every round.
No, it wasn't any good. Especially compared to Mario's Mascot RPG tie-ins. Take a bland RPG with an uninteresting and slow battle system, give it bad music, stick some bad Sonic character models in it, and there you go.