I'd say they're most like the early Final Fantasy games, with your party on one side and the enemy on the other in turn-based battles. They're best known for their nice and numerous anime cutscenes and endearing characters. The graphics are simple SNES quality, but still charming. They're definitely worth playing, and I see them fairly often at used game stores, so they're probably not that rare.
I have a hard time locating them at local game stores! I've always wanted to play either title on the psx, and I feel ashamed for having not played them and calling myself an RPG junkie
Someday, though, I'll submit that bid on ebay to get a copy.