Jeez, I've got no idea. Chord progressions used to be my number 1 priority in prog, and I love finding stuff that shouldn't work but does. For example the bridge in "The Spirit Carries On" which is Em-Eb-D-E-G-Em-Bm, or Nick Drake's "Time Has Told Me" has a great chorus of E7-Eb-Ab6-D. Genesis always have incredible ones popping up all the time, too many to list, as do Procol Harum and the rest of the big 6. There's no way I can decide, so here's a few more short ones off the top of my head:
Sufjan Stevens' "Prairie Fire": A-Am-Bb-G.
Genesis' "In The Rapids": Asus2-G#m-F#sus2-Dmaj7.
Procol's "Wreck Of The Hesperus" orchestral break.
Steven Wilson's "Luminol": C#m7-Dmaj7-D#m7-Dmaj7; or "The Raven": Ab-Am-F-Cm-Ab-Am-F-C.
Moody Blues' "Dawn": Fm-E-Eb-Eb-Dm-G- C / Eb/Bb /- F/A / G /.
Rush's "we will call you Cygnus" part: G-Bm-F-F#11