Oh I don't know. But having listened to them since I was about 10 I feel that the one I can listen to every single day, which doesn't mean it's the best, is Animals. And I say this as the biggest fan of Syd who was so happy to hear “Rhamadan,” finally.
It's that song “Dogs” mostly. Sick parody of jazz funk and prog jazz from around that time. That mid section which is a keyboard solo (or electronic world, really), where dogs melt into human voices melting into the primordial slime, for some timeless time out of time. It's beyond Orwellian prosopopoeia. It's humans melding with nonhumans in an incomprehensible, nonconceptual way.
If you take the train from Sutton to Victoria you pass by the gigantic Battersea Power Station, but before you do that you pass through the lands of early drum and bass, where I used to live. Something about those siren-like sounds on “Dogs” and elsewhere on that album. Secret, melancholy London, side by side with the official one. Geniuses in tiny flats on their computers in 1992.
But “Dogs.” The mid-section. Stone, stone, stone, stone...the syncopated echoing barking...the unbelievably well placed and tuned out-of-tune whistle. Good grief.