My first Tales experience was last summer with Tales of Graces F. I loved it. I plan on buying Tales of Xillia. Apparently Symphonia for the GameCube is the most critically acclaimed of them all so I'm wondering if I should jump on this? I might even try the sequel (which according to GAF, sucks).
The gameplay difference going from Graces to Symphonia is quite the jump.
example: http://www.youtube.com/watch?v=k94ft_dRljM#t=0m30s
It does, in my opinion, have a better cast of characters (along with some bad eggs) and a better overall story. But it plays very differently from Graces.
Symphonia 2 has a much weaker lead character than most Tales games, and they replaced a party with monster teammates. It's an okay game but it made a lot of changes people didn't care for.