I am half looking at a real MF - the D800 would be just a faux MF. Would rather have a 80Mb MF
Good luck finding that for $3000.
D800 is a killer in resolution, DR, and even low light... its resolution and DR compares to MFDBs and its low light performance compares with D4. What more can you ask for?
Price is not the issue - I would expect somewhere in the region of $35k which is what you have to pay for the best.
I dont think in my remotist dreams think that a 36mp D800 will compare with a 80mp MF.
Low light performance? Iso 200 is fine for me with a MF. You dont shoot sports with a MF
Sorry, but it was YOU who compared D800 to MFDB. Highlighted above in red, you said that you were "half looking at a MF". That is comparing, still.