This is the game that got me into RPGs, and the reason I bought a PS2 and a Gamecube.
SoA is immersive and fun, and certainly worth buying, if you still have a Dreamcast. If not, the Gamecube version is equally fun, and virtually identical, except for an additional sidequest.
The storyline is reasonably typical, ie. Save the world, blah blah blah, but is set apart by interesting environments and varied battles (nautical-style battles on your airship and traditional turn-based creature battles). The magic system is your standard element-based fare, but doesn't get too dull. You may find yourself using a White ring (to block random encounters) part way through the game, but resist! Avoiding battles can limit progress in sidequests, meanining you can't acheive 100% completion.
9/10. All in all, excellent. Still waiting for the long anticipated sequel... It was announced when? 2003?