I have a Dell P2715Q together with a Dell mount for my desk for almost a year now and I love it, especially with the mount. This display is 4k and you can use it as a retina display alltogether with a MacBook. I can't use non retina displays anymore. The colors and brightness are wonderful.
We use these monitors at Yeti.co as well and I can't recommend them enough. The color reproduction and the sharpness is something you can't come back from after having one.
I have a Dell P2715Q together with a Dell mount for my desk for almost a year now and I love it, especially with the mount. This display is 4k and you can use it as a retina display alltogether with a MacBook. I can't use non retina displays anymore. The colors and brightness are wonderful.
Here are two pics of my setup:
https://c2.staticflickr.com/6/5629/20971104293_f676c39d66_b.jpg
https://c2.staticflickr.com/6/5726/22280222241_8f148b995a_b.jpg