I used Sailfish OS and so did several of my family members for many years. The "vanilla" Linux OS aspect (besides using rpm) makes it trivial to set up things like dnsmasq-adblocking, firewall rules, etc.

Unfortunately, the Sailfish UI itself feels "different for the sake of different" and not because it's functionally more useful. I think the UI is pretty ugly and difficult to navigate. Anyone who "loved" Win8 tiles and/or Windows Mobile flat monochrome UI always praises the SailfishOS UI but outside of that small group I don't think the UI is that functional. It's definitely eschewed it's MeeGo / Nokia N9 UI heritage.

What always surprised me about SFOS is despite running on some pretty decent hardware, the UI always felt sluggish, especially given it's kind of reversed-big-text UI paradigm which shouldn't take much work to render.

I'm glad there's an alternative, but sad it's hasn't seen a reasonable set of UI improvements despite its age.