Here are my first impressions of the Stellia:
Overall the Stellia has a perfectly balanced sound and is very suitable for long listening sessions. For me, a very little bit more subbass would have been fine, and in return a tiny bit less high mids. There are some tracks where the “s” and “sh” sounds of the singers are too pronounced. If I had a DAP with good EQ (like the new LPGT), then that would be achieved in no time, although of course I prefer to use no EQ, if it can be avoided.
Which I’m not really satisfied, is the sound attenuation from the outside (this has made my old Oppo PM3 better as well as the CA Cascade). Also, the Stellia loses a lot of sound to the outside and disturbs, especially when listening to louder volumes, the people in the same room. In my opinion, therefore, the term “closed-back” is not right. It should be called “Semi-Open” or “semi-closed” for my sake. But “semi” - something does not sell well I guess 
The earpads themselves are incredibly soft and adapt well to the shape of the head. Even with glasses (at least for me) no problem and no bass loss, which I very much welcome. Nevertheless, it would of course be fine if the headphone had been a bit light weightier. On the other hand, this is hardly possible to produce without giving up high-quality materials. Since I prefer to do without cheap plastic I´d rather take the weight into account. But if Focal still finds lighter quality materials, I do not mind.
The cable is ok. When the music runs, you can hear no more cable noise. It is just too thick and inflexible, but at least high quality. I would have liked, for the price of the Stellia, an additional cable with 2.5 balanced, on which one could put on a 4.4 adapter. Of course, if Focal had managed to add even lighter and more flexible cables than those that shipped them by default, that would have been fine.
All in all, I could have done without the luxurious packaging, and would have liked to have better cables, see above.
The case is great because where the cable is, my DAP fits in!
The Stellia is more than enough to drive with my Calyx M. The processing of the Stellia is great! It is the first “closedback” - cough cough - headphone that is not foldable, which I have considered. In fact, I will use it every day as I walk through the city. So far, I’ve heard with the InEar ProPhile8, the Stellia is an upgrade in every way, but not, as mentioned, in terms of isolation.
All in all, however, a 1A product.