It's one of the best JRPGs on the PS2. I was playing it non-stop until I finished it.
The only problems I can point out are the camera angles (such a obvious throwback), low difficulty (auto-battled 90% of the time) and in my opinion, it's somewhat impossible to get all SODs without using a guide on first playthroughs...
Other then that, lovely game. Great story and cast of characters. The large scale naval and ground battles are very fun. They also added a timer to the duels which adds a little spice to it.
EDIT:
@ astr0creep
Consider playing SIV, if you can get past the system changes (4-player battles, etc) it's really not that bad of a game... I'm enjoying it.