At first it was the former, then the latter. )
Well in that sense Macs aren’t too different from any other laptop. HDMI worked just fine. I was also trying to connect a USB-C monitor through an HDMI adapter, which didn’t quite work, but I think that might be the case with other laptops too (it’s probably a driver issue). From the desktop experience point of view, KDE handles multi monitor flawlessly, can’t think of any complaints.
Like the other reply suggests: look up which drivers you got (mainly the wlan, bluetooth and the camera), and see if WL or facetimehd support those. It wasn’t that much of a pain with the drivers though. Also, find out whether you have the “over the internet recovery”. If not, I would probably avoid deleting the recovery partition, and opt for a dual boot (or manual partitioning).
Yeah, I believe these were one the first retinas with 200+ ppi. Honestly, for a person who spends most of the time staring at a code or a text, hidpi is basically a necessity for me at this point. So the fact that slack or vscode had such a bad support for fractional scaling is a huge deal for me. (Wayland fixes this in some instances as I mentioned)