Ive been using nix-darwin for over a year now after using nixos with flakes for a bit. I now have a singular repo with multiple machine configurations. Nixos for my home server, nix darwin on a macbook air and a nix darwin with a work config. This allows me to have common programs on all machines but also overlay some specialised packages and programs in certain environments. After climbing the initial mountain, its been very satisfying and things just work. My work laptop died recently and I was able to be fully up to speed in a fraction of the time it would have taken me otherwise.