I’ve just started using NixOS after a decent run with Ubuntu Server + i3
I first dabbled with RedHat 4.x (the one from 1996). It was not easy. Nothing worked and it took ages to fix without Internet (because the modem would never work out of the box). Because I only had one computer I had to boot into Windows to read the documentation, reboot to linux, try a few things, reboot to windows again, etc, etc.
Dual booted somewhere from RedHat 6 (1999) but still used Windows as main OS.
Took all the way to 2005 when I started using Ubuntu until I finally ditched Windows. Have not used it since. Changed to use SuSE for a short period, then into slackware for a couple of years. Then a brief venture into Arch but I have problems with rolling releases (it is always something that breaks). Back to Ubuntu 12 or perhaps 14.04 + i3, which I updated to 16.04 and then 18.04 and now finally had enough of it and went distro hunting again for the first time in many years.
After trying and discarding, Ubuntu 20.04, PopOS!, Regolith and Manjaro (still don’t like rolling releases) I figured I give NixOS a try.
So far NixOS has been outstanding for my use-case. I have a very particular setup and now I can have a configuration.nix file containing my entire configuration they way I like it without having distro’s trying to second guess my preferences. And it is trivial to replicate to other machines! Now I only need to find out how to get NixOS onto my AWS server systems and I will have peace of mind.