I finally got a copy for a sensible price a few weeks ago. I'd give it a strong 8. It's really good, plenty discrete for my tastes (lots of orchestra/brass parts isolated in or favoring the rears) and the material's never sounded this clear, but I still prefer the old quad mixes of
The Singles and
Now & Then.
One interesting thing I noticed when comparing the quad and the 5.1 is that the physical arrangement of the song "This Masquerade" has basically been flipped front-to-back. The quad mix had the orchestra and flute upfront, the drums in right rear, and the piano in left rear. The 5.1 has drums and piano in the front, and the flute and orchestra in the back.
"This Masquerade" (5.1):
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"This Masquerade (4.0):
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