There's always a disparity of opinions when it comes to any major TOTL launch; it's pointless to fight over it. The Abyss even has its avid supporters (though they're sometimes too embarrassed to be forthright about it); the HD800 has vehement detractors. Even when it comes to the factual realm of what a headphone sounds like in the most objective terms possible, there's still room for wild varations.
There's no one thing to point to for an explanation of this, but we've covered almost all the contributing factors.
Variation in source and amp equipment can vastly effect our opinions of our newest purchases, especially if our equipment isn't electrically well-matched to what we've bought. Somebody driving their AD off a uDAC2/cMoyBB setup is going to have a vastly different experience from somebody with a Bitfrost Uber/Mjolnir combo or somebody who uses a WA7.
Somebody whose main cans are open will have completely a different soundstage experience from those who use closed cans almost exclusively.
Somebody with a lust for midrange will hear things differently from a basshead, since they're both being more critical about different sonic ranges.
And so on and so forth...
The "buy it yourself" argument is valid, but it doesn't take into account the fact that the majority of us can't just plop $700 plus shipping down on a whim and hope that we like what arrives. Regardless of Dan's great return policy, that's a lot of cash to have tied up at once. Meets are great, but they're noisy and you tend to only be allowed a cursory listen before passing it onto the next visitor.
Edited by ssrock64 - 10/17/13 at 7:14pm