I've only played the GBA version of Phantasia, and Eternia on the PSP. Every other game has either been on a system I don't own or just not released outside of Japan, the games for the portable consoles being a prime criminal for that one.
That said, I did really enjoy the ones I have played, and Symphonia is supposed to be really good.
That said, I did really enjoy the ones I have played, and Symphonia is supposed to be really good.