I played it twice, both times on the DS. After the first playthrough, I felt it was a waste of my time, but at least I beat all of the FFs at last. I recently wanted to play all the FFs in succession, though, and once I reached III, I was blown away. The battle system still annoys me, but at least less than the last time, however the story is just so complex after I and II... Besides all the stuff about morality, life and death, etc. that everyone seems to mention, I loved the world for what it was. I later played FFIV DS - which I always thought to actually be pretty dumb and ridiculous at times - and was again blown away by the depth the creators have given the game with basically just a few tweaks. Really, I think they should keep remaking FFs for the DS since the console seems to be meant for those games...

Back on topic, I don't consider FFIII to be one of the best FFs, but it was definitelly way ahead of its time, and still thought-provoking after so many years.