This is a rough final. Relistening to both tracks, it's pretty clear that these are both true exemplars of the ideal metal epic -- long, winding musical journeys with light and shade, memorable but aesthetically distinct segments that flow naturally into each other, and not a dull moment to be found. I think these two songs were the best of all the nominees, and either track would be a worthy winner.
"A Change Of Seasons" really puts the best of Dream Theater on display. LaBrie stays on the rails and doesn't try to wail so much that his enunciation falls apart, and he gets to spend a fair amount of time in his warm ballad voice where he typically sounds the best. The musical parts are challenging without ever becoming masturbatory, and most sections are pretty memorable.
"The Odyssey" is a similar showpiece for Symphony X, with Allen mostly avoiding the over-the-top scenery chewing he can sometimes fall prey to, and the musical parts serving the song and staying interesting without going overboard. It does suffer a bit from the band's typical low-rent synth sounds in the early going, but the vocal melodies in particular seem to land harder and leave more of an impression than on the Dream Theater track. And in the end, that advantage and the even grander scale of the Symphony X track give it a slight edge.
So, sorry The Dillicent, your nominee was worthy, but MrDickerbooleven's choice takes this one. Winner: Symphony X - "The Odyssey"