I first installed guix (using this guide) onto an old desktop I had to get a feel for it. Then, when a system update on my laptop (manjaro) went sideways I installed guix onto that and never looked back.
It does have some caveats. Some packages don't exist in the official repo, but thankfully you can have as many channels as you want and get packages from other repos (nonguix being the biggest). Ironically for applications for with a guix package doesn't exist, I use nix.
Some DEs aren't available (KDE forex).
Despite the above issues I really like guix. I like the transactable nature of system and package upgrades (same/similiar functionality as nix). J
Just like nix your system config is declaritive (in scheme a file/files) and you can rollback configs. I'm more likely to try things/update my config because I can just rollback if something goes wrong.