My favorite DT album over-all. And no, just because it's their longest, or that it happens to be a double album (which, in the digital age, really has no meaning since songs escape physical medium, the idea of "double album" is only relevant to separate releases, like what Guns & Roses or Green Day have done).
Anyways, back on track - it's got the title epic, a Top 5 DT song for me, and the other 5 songs are just Top 20 songs, all of them, even "Misunderstood". They cover a wide range of material, sounds, feels, and genres on this album.
You've got the heavy metal riff-chugger (and beginning/best part of the Twelve-Step Suite) in "The Glass Prison", the piano-riffic and soaring "Blind Faith", the experimentally challenging "Misunderstood", the politically and morally driven Tool-esque rocker in "The Great Debate", the tear-jerking ballad with "Disappear", and the prog rock symphonic masterpiece with the 8-part title track. It's all here, and in great form.
Honestly, while the last 5 albums have had great songs, as a whole, I'd say nothing has compared to SDOIT since it's release. 8VM sort of came close, and BC&SL was pretty good, but as a whole album....nah. There have been par/sub-par moments or songs on each of the last 5 albums that have brought them down a bit, but SDOIT was as near-perfect as Dream Theater have gotten for me.
-Marc.