I think every part is great individually, although none would quite crack top 20. Together I wouldn't rank it any higher though, as it's not really better than the sum of its individual parts. And to judge it as a song, there's very little continuity from one part to the next, in regards to tonality, rhythm, tempo, or even basic crossfading in the case of Voices > TSM. It just hard cuts off entirely before TSM, which I've always found annoying and badly edited even for a song to song transition.
So to answer the question, I'd probably rank it about the same as I'd rank the best individual part (which would either be Voices or TSM). Somewhere in the 20-30 range, which for DT is still great, but it wouldn't compare to the longer epics that were written to work as songs.