As long as what you want to do is already in nixpks it's extremely easy, once you stray from that you need to start learning how all of it works, it's not the best in terms of documentation & straight forward concepts, but I've been running it at my main desktop for 6 months now.

Sometimes it shines ex:

I messed up my x11 config as well as drivers and just booted into the previous generation like it was no big deal

I needed to install a version of electrum that was only available on a specific git commit. I just specified the commit and booted into a shell with it

Sometimes it sucks:

Learning to package arrive 3rd party software can sometimes be really complicated and it might be the only way forward.

Lots of steam doesn't work out of the box compared to Ubuntu.