Hm, in this video from RMAF 2015 the Pioneer rep says that they were going to bring them to the North American market starting in Spring 2016.
http://www.innerfidelity.com/content/canjam-rmaf-2015-pioneer-se-master-1-flagship-headphones#xPaHofHtAXxTJKeE.97
Then again, he also says that they've been available worldwide for a couple of years, which definitely doesn't add up, so maybe he just doesn't know what he's talking about.
I would also be interested in such a comparison. From what I've read here (and owning the Pioneer), it sounds to me like Master1 does about everything Utopia does in regards to SQ, BQ, comfort while exceeding it in terms of bass quantity/quality and soundstage, but I'm admittedly biased. Still, so far I get the impression that, obviously
very generally speaking, SE-M1 > Utopia > HD800(S) while Elear > TH-900, but I could be wrong, of course.
In any case, the concept is interesting, the Focal guy in the video seems to know what he's talking about, and I'm curious to see (i.e. hear) if Focal has succeeded in creating a headphone with a "speaker-like" sound, which I would probably be inclined to like. I know Pioneer already has (and for almost half the price at that -- which is still a LOT of money, mind you).