I use a 42.5" LG 43UD79 4k monitor as a computer screen. It's fine for work/text and non-AAA gaming. For photorealism/movies the blacks or vividness of colours is not as dramatic as TVs so I don't use it much for that.

Why is a non-4k one preferred? I notice it's discontinued now and there are newer LG 43" monitors (with maybe better blacks/saturation).