I have listened to so many amps for the hd800. And it's all about perspective of what does it for you. Yes some amps just do not do well with the hd800 and those are the majority , but it is still about your choice. You can read all you wish but you do need to listen yourself on music you know . If you cannot I understand but then you are buying Soly on reviews . And they are at the very least subject to conjecture.
And the DAC is important too , although people here will say if its good its just a pass through, I say bull. I have an denon rec about 6 years old top stuff at the time and it sounds great with the hd800 . But the newer stuff I own adds so much more detail with out really changing the sound signature . They are analytical first and foremost , so they will be bright . If you want them to be dark , get a different headphone.
Good luck , I do like the WA22 stock tubes and woo,s DAC as well. But that's my opinion LOL.
AL D