Considering Moving to Nix OS (for eventual second computer). Advice?

I currently have Fedora 44 KDE set up as my daily driver on my laptop, and am not looking to switch on that quite yet (I have it set up as I like, it has some copr repos enabled, etc). I was reading up on how to properly reproduce my system in case of data loss, and love the idea of being able to copy a couple of config files and almost completely reproduce the system. (I love the thought of being able to see everything laid out in a config file as well; I feel like that will help me keep better track of what’s going on with my system).

With this in mind, I expect I’ll get a desktop within a year or two and am considering installing NixOS on it. What will the biggest learning curve be? Any advice? Is there anything I’ll miss from Fedora?