Mini I only ran T8 live, never installed. It still has El Capitan on it.
For the MBA, I now have Ubuntu 18.04 installed on it, before that Fedora 28 and before that Trisquel 8. MBA still has MacOS on the side, dual boot. With T8 I used rEFInd, Ubuntu and Fedora recognize and boot MacOS (Grub Menu).
Most things work on MBA. I didn't see any issues with Mini. Hard to say about post-installation as I never proceeded to put it on the hard disk.
