I quite enjoy it!

Being able to rollback any change I make to the system, either package changes or system configuration, makes it completely unbreakable and provides great peace of mind. It means I can fully enjoy its rolling-release nature without worrying.

Having my entire system configuration declared in a single, robust programming language (Guile) across a small number of files makes it very easy to understand and just stick into source control to reproduce.

Being able to hack on it in a lisp (scheme) is the cherry on top, along with the great emacs integration. I would highly recommend it to any lisp/emacs/gnu enthusiasts.