The only thing in jackett that I miss when using prowlarr is support for a selfhosted magnetico instance, because otherwise I don't think there's any way to add magnetico as a source for sonarr/radarr. Granted I don't miss it much because my magnetico postgres DB shit the bed and I've been putting off recovering it because my DB is 100 GB and I kinda don't want to deal with it.

I do like that prowlarr will connect to sonarr/radarr using their API and can be set to sync all the indexers set up in prowlarr into both sonarr/radarr automatically based on which ones support movies or TV shows, so that's what drew me to it. Makes adding and removing torrent sites less work.