It's really nice, but text can be hard to read without scaling or enlarging it. I haven't looked at any other 4k or 5k displays, but I think a 30" 4k would be much better. Sadly those are really expensive at the moment. The P2715Q is the best IPS 4k monitor in the price range, plus I got a great deal on a used one.
Even with the text issue, I think that it's still a significant upgrade over the Thunderbolt displays I was using before (I was using 2). Not quite as huge as going from my previous non-IPS 1920x1200 monitor to 2560x1440, though.
