I've tried out this device and overall I prefer it to the Chromecast with Google TV. IMO, this Onn UHD box is the overall best choice for most YouTube TV subscribers given that its remote has a dedicated live TV button that immediately launches YTTV, plus has channel up and down buttons for channel surfing in that app (as well as in other apps such as Live Channels). YTTV runs well on this device, as did all the other ones I tested.
Google Assistant also surfaces content from YTTV via voice searches from the remote, although it doesn't work as well in that regard as you would expect. (For instance, saying "Big Sky" resulted in the Assistant launching the regular YouTube app to live stream the UK's Sky News channel! Then when I specified "Big Sky on ABC," it did show results for that series with options to launch it in Hulu and FuboTV, but not YouTube TV. Typical Google dysfunction.) There's also a separate voice search functionality, invoked on-screen from within the YTTV app, that searches *only* content in that app (i.e. it does not use Google Assistant) via voice input from the remote and that feature works reliably well.
And unlike Roku or Fire TV, you never have to worry about Google withdrawing support for their apps on this device since it runs Google's own Android TV.
It even incorporates most of what's good in the newer Google TV system -- Google content recommendations from the free and subscription services you use (including YTTV) and the Google cross-app Watchlist -- via the Discover tab on the Onn's home screen. Meanwhile, you still get the customizable Android TV main Home tab with a top row of your favorite apps and a cross-app Play Next row under that. I found that it reliably displayed the next available episode, and partially watched episodes/movies, from content launched within the HBO Max, Apple TV, Peacock, and Xumo apps. It didn't seem to work with Prime Video though. Also doesn't work with YouTube TV, although IMO that's a good thing because if you watch a lot of stuff on there, your Play Next row would be constantly clogged up with partially watched live TV shows. Clicking a title in Play Next immediately launches the video in whichever app it belongs to. Long-clicking a title in Play Next gives you the option to delete it from the row.
The remote feels better and is simply better designed than the one that comes with the latest Chromecast. Had no problems getting it to control power, volume and input switching on two different TVs I tried it with.
Honestly, this little $20 box is the best choice for anyone looking for a quality Android TV device but who doesn't care about Dolby Vision, Atmos, auto framerate switching, or native audio passthrough. If those features are important to you, you'll need to pay more for either the latest Chromecast or the Nvidia Shield TV. To get a similar-quality Roku or Fire TV device (4K HDR with voice remote), you'll normally pay at least twice as much and, IMO, it won't be as optimized for heavy YTTV users.
