I’m new to NixOS, just installed it a few days ago, so I can’t say much about it’s pros and cons, but the installer was easy and I installed and booted into the new system very quickly. I think it might have been udpated in the past year, because I am watching a tutorial video from a year ago and he installs it via command line from the live iso.
edit: it also gave me a default configuration.nix which I’ve just been adding to (to get nginx with letsencrypt running, plus extra packages I wanted installed)