I've listened to the HD800 (which I own, modded according--more or less-- to Anaxilus/Tyll directions) with the Beta22 (mine is a Nugget Audio unit). It's a great system, very good sound quality, but a bit brittle, not really involving and enjoyable in the lush-musical sense. Sound-wise it's awesome, plenty of detail and rough quality. The Gilmore Reference (kind of GS-X) or the Luxman are more musical and enjoyable. It all comes down on what type of sound you enjoy and like better.
The 3000ANV are nice cans, but not really in the same league of resolution, detail and balance as the HD800. For closed cans are fun though. Still unsure if I like the L3000 better.