I have a samsung serif QLED (because I am a prime poseur) as my second TV and its UI/firmware is hands down the best smart TV firmware (compared to e.g. hisense UI/firmware, humax, sky, or virgin TiVO) I have ever used. can't say I've noticed the ads but I am semi-glaikit
it's a 2020 43". the UI is silky smooth - my main TV (4K hisense 55") is an absolute dog in comparison (with the others I've used - sky/humax/virgin TiVO - not much better...)
I have a samsung serif QLED (because I am a prime poseur) as my second TV and its UI/firmware is hands down the best smart TV firmware (compared to e.g. hisense UI/firmware, humax, sky, or virgin TiVO) I have ever used. can't say I've noticed the ads but I am semi-glaikit