Well, I have a 58" 4K TV as a monitor and I sit about 2 feet from it. And then I have a 135" projection screen and sit 10 feet from that - I would prefer sitting even closer but if I move any closer than that, I can see the pixel grid of my 1080p projector, so I’d love to have a 4K one. In cinemas, I can always see the pixel grid as well and it’s really annoying. 4K definitely makes sense for screens.

But even sitting 2 feet away from my monitor, I can’t really tell the difference between 4K and well-upscaled 1080p. Especially when you add compression.