I like it design wise, but like a lot of these "de-clutter" tools it defaults to disabling security features without warning and will break some sites while making most sites slower. Plus it ironically installs a bunch of browser addons. So if you hit next, next, next you'll lose: Google Safebrowsing (security), malware scan (security), DNS over HTTPS (security and sometimes functionality), Automatic Browser Updates,…
Anyways, the people who made this would say that Mozilla's current defaults get 0/10 from them and are simply awful, and that using them means your browsing experience will be objectively worse and less private.