I loved BBS. I hate how they are reluctant to make a 3rd titles as they cash cow the other hand held titles for all they're worth, even when they suck. BBS is the only proper one. The only thing I hated about Birth By Sleep, aside from overly fluffy cutscenes, was that to move on in Mirage Arena you HAVE to advance in their stupid racing game... I swear that shit is less intuitive than Mario Kart on the SNES.
The secret bosses for that game, if you plan to do them, good luck. You may wear out your dodge button. :P