I just got these headphones and have been listening to them for the past few hours. Maybe it's still the "honeymoon" period, but they are definitely my favorite headphones. I also own HD6XX, Aeon Flow Closed, Ether Flow, and K7XX. I have owned the TH-X00, but sold them recently.
I am not a high-end audiophile, but I am a professional musician who loves listening to all kinds of music. I listen to music on my computer with iTunes, though a Jotunheim amplifier with the DAC module. I'd like to present some comparisons to you. I define "fun" as bass presentation (not necessarily extension) and punchy dynamism. I define "detailed" as being able to hear individual instruments in their recorded acoustical space clearly. When I evaluate "comfort," note that I have a fairly large head, I wear glasses, and I have some neck and shoulder problems from the last 10 years of being a professional violist.
HD6XX are less fun, less detailed, and slightly less comfortable (clamp force too much for my big head and glasses).
Aeon Flow Closed are less fun, similarly detailed, and slightly more comfortable (see update).
Ether Flow are less fun, more detailed, and slightly more comfortable (see update).
K7XX are less fun, less detailed, and similarly comfortable.
TH-X00 are similarly fun, less detailed, and less comfortable (if memory serves).
Of all these headphones, the Elex has the best balance of fun, detail, and comfort. The closest competition is the Ether Flow, which have better bass extension, but not as punchy as the Elex. They are "laid back." The Elex also seem more "open" than any other headphones here. It's almost like listening to speakers.
Here are some tracks that used for direct comparison:
Pasadena Symphony: Rachmaninov: Symphonic Dances: non allegro (the Pasadena Symphony binaural recordings are some of the most underrated classical recordings out there).
John Williams: Harry Potter and the Prisoner of Azkaban: Quidditch, Third Year
Daft Punk: Tron Legacy Soundtrack: Outlands, Pt. II
Massive Attack: Mezzanine: Angel
Yosi Horikawa: Wandering - EP: Letter
Blues Traveler: Four: Hook
Elex has very nice build quality. The nicest of all the headphones I've ever owned. I wish the balanced cable was longer.
My dream cans would be something as detailed as the Ethers, but as fun as the Elex. Clear maybe? My wife would divorce me if I bought those just to find out.
Hope that helps. I'm sure lots of people will tell me how stupid and wrong I am, but these are my opinions.
UPDATE: I've had these for a few days now. I discovered how to wear them and they now match the comfort of the Ethers and Æons. I've always worn headphones in such a way that the headband rests at the crest of my parietal bones. This works for other headphones, but for this headphone, I need to place the headband further forward, along the coronal suture. This also makes the ear pads line up better with my ears. Now it's almost like I'm not even wearing headphones. Maybe this is obvious to everyone else, but not me.
UPDATE 2: I've had these for a number of weeks now and I no longer listen to them. I fell so in love with the Focal sound that I ponied up and bought a Utopia, which is what I listen to constantly. I was able to go to a retail store and compare the Elear, Elex, Clear, and Utopia all from the same amp. I may give the Elex to my brother. It seems to me, based on reading other reviews and comments that either you love or you hate the Focal sound. I just happen to love it. It commands your complete attention. Maybe if you're looking for something to play in the background, go for a relaxed planar sound. Now my next purchase will be a nicer DAC/Amp combo. Somehow I get the feeling that the Jotunheim isn't pushing the Utopia to its full potential. The Elex and Utopia are very similar in build and comfort, but the Utopia just has more depth, detail, and focus. Incidentally it's on sale right now (until the end of October 2018) for "just" $3000. And you get a $1000 player thrown in, which you can sell on ebay.