I've never owned a pop up but have owned 5 hard sided campers. I had considered pop ups many times and researched them extensively. My main conclusion was that they are more utilitarian and spartan. Functionality over comfort. The deal breaker for me was always the bare bone minimum dinette seating designs. Having a 90 degree seat back angle consisting of a 12 inch tall back cushion with minimal thickness just didn't appear comfortable for extended periods of time.
I have followed some adventurers on YouTube who owned pop ups and they all mention issues with condensation in certain conditions.
This is obviously just one man's 2 cents worth :)