I was holding off getting a Cosmo until cellular support in linux was a thing. It was added in July so I placed an order for an in-stock unit and received it in just a few days (drop-shipped from HK).

Phone calls and SMS messaging seem to work OK. Working on testing mobile data now.

So far I am cautiously optimistic. Adam Z. Lein posted a review where he recommeded using mtrack to make the touchscreen function like a touchpad which makes the full desktop experience very usable. link

My biggest concern right now is the success rate I've had just installing and running software in linux. Kodi, cairo-dock, firefox, octave all installed & ran fine. Libre-office was also successful, tho I had to hold the SMS messaging package or apt would try to remove it. VLC, blender, stellarium all failed to run with various OpenGL errors or outright seg faults.

I don't prefer KDE so installed the MATE desktop and that worked fine. When I tried to change the display manger the system failed to boot, so I need to reinstall again. There is a problem where the screen occasionally freezes. Sometimes the mouse will still move when this happens, but so far I haven't found a recovery option from this frozen state outside from holding the power button for 10 seconds and rebooting. There are no F-keys so changing TTY isn't an option. Next time I'll setup an ssh server so I can try that.