Just go a new TV yesterday, a 4K TV from LG, and - for the moment - hooked it up to my old Apple TV 4, outputting 1080p. The TV scales up the picture very well, and the quality - based on yesterday's evening viewing - is excellent.
But, I still would like a new 4K enabled Apple TV. I "refuse" to buy the current one, with 3+ year old tech, so Apple needs to release an updated version soon.
In the mean time I've set up WebOS on the LG TV today, and are currently conducting an experiment on whether I actually _need_ a new Apple TV, or if the built in apps are good enough. The longer it takes, the stronger the chance that I get used to WebOS, and don't miss the Apple TV enough to justify a purchase. (Or - on the other hand - frustration might build up, and I'll but the next version at any price...

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