nVidia Shield TV is pucker, and you can run games on it too. More expensive that a cheapy chinese thing of course, but not a lot of money in the scheme of things.
I can stream 4k content off any dodgy server with sufficient bandwidth and it plays beautifully. 1080p live broadcasts are a doddle.
I can vouch for this. Although I am on my second one after the hard drive failed (known problem and Nvidia replaced with no hassle, even sent me an extra pad)
Matrix TV Browser and your IPTV and you're away.