Obviously not an apples to apples comparison, but when I can listen to the Quads on the desk as loud as I like, I prefer them to the 800s. Especially with lower-fidelity pop and rock music. They're just more fun.
But I still like the 800s more than any other headphone I've had a chance to live with.
Drove in to Worcester to get lunch at The Sole Proprietor. Wormtown is a dump generally, but that's one awesome old-school seafood place. Plus they have the world's largest inflatable crab!