These are everything you'd expect from a flagship headphone, only MORE, because some flagships have come to disappoint me, even from the more expensive brands. In a lot of markets, I find there is often one brand that stands out as cheaper yet better, and in headphones, I think it's Audio-Technica. I should say I've not heard any planar-magnetic headphones, so I'm not comparing with the BEST. But comfort, sound, and price wise, you can't go past the ATH-AD range, and this is the top of the lot.

It took me a while to warm up to this set of ATH-W1000X, because they are just so warm compared to what I'm used to, so it sounded like they lacked the clarity of my other sets (which, to be fair, are excellent and very expensive sets such as the Beyerdynamic T1 and the open ATH-AD2000X) - but it's not that the clarity is lacking, it's just that your ears are full of warmth and you don't notice that EVERY detail is there. My title, pros and cons say it all really - it is not a cheap set, but I firmly believe that they're the best closed headphones under $1000 I've heard, so given that, they're a steal at about $450 US/$550 AU. If you are really savvy, you can get them cheaper, so that's a REAL STEAL then.
Sound staging is actually better than many open sets I've heard, including ANY Sennheisers (HD650s come to mind for a closed sound from an open set), and similar staging to the ATH-AD900, which is saying something.
A great set of headphones, without a doubt.