There are so many things that seem to work against the HD800. Do they really need a super DAC and a mega expensive amplifier? And are they really so bad with every musical genre other than jazz, acoustic and classical? They don't sound like headphones for your average music enthusiast. They sound more like headphones for people who attend dinner parties and go to see symphony orchestras.
I've heard them through an HRT MSII+ and Bottlehead, as well as the same setup through a Burson Soloist that was amazing. The Soloist is a great all around amp but I've honestly been happy with the HD800's with much less. Sure there is a plethora of "better" options out there but the fact that the HD800 still stood head and shoulders over my entire "mid-fi" collection still makes it a solid setup IMO.
The cheapest amp I've been pleased with is the NFB 12 by AGD which doesn't exist anymore, replaced by the NFB 15.32, followed by the Matrix M-Stage, and Gilmore Lite. The best amp I've heard with 800's are WA5 and DNA Stratus, both in the same room, same headphone.
It scales AMAZINGLY well compared to the orthos, save for the HE-6 (which doesn't require a headphone amp, more like a speaker amp) with just about anything, so I completely understand that there is a lot of potential untapped if you don't want to spend the big money, but I am of the opinion, whilst probably the unpopular one, that it does not take mythical budgets to make them sound "good".