I recently tried streamio on firestick, the app worked great in terms of ui and responsiveness but the services it connected to never worked. 5 was on it by default and each allowed me to browse movies and series but when i attempted to watch them it returned an error or buffered forever. I also tried with and without a vpn to see if that affected it. Personally the way that still works best for me is using a browser such as sideloading firefox and then visiting the websites using a vpn like you would on a laptop
Edit: while im here, sideload the newpipe apk. Amazing frontend for youtube
Iv been using odysee for a couple years and never had an ad on the ios or android app. Nor in the browser. (In video sponsors dont count). Odysee ftw i much prefer when creators i watch use youtube and a alternative platform like odysee