Edit: Monitor prices can vary significantly based on the time and the place you buy it from. I payed about $800 less than MSRP. It was still super expensive.
I really like it; 4k is enough pixels to be pretty sharp, even for high-contrast stuff like text, as well as enough room to able to cram a bunch of stuff on screen. Also, my brain is kind of bad and as a result I am able to comprehend what I'm reading if the text is huge. I have not measured the latency on this screen yet, but FWIW I was able to beat Donkey Kong Country 2 (a pretty challenging game) with the MiSTer plugged into it.
People have told me that dedicated monitors are better though, both in refresh rate and just in general for more desktopey stuff...do you think that's true? How much more worth it do you think that is? I've debated buying a dedicated monitor, but getting something of a comparable size and resolution is pretty pricey.