As I needed a monitor for my 2013 13" rMBP, I decided to get Dell's new U2515H. And would like to share my experience. I also have a Dell P2415Q and was not happy trying to get it to work with 2013 13" rMBP, 30Hz refresh is too slow and I seem to personally have an issue with 52Hz ( gives me a headache ).
So the U2515H
Pixel pitch .2197 works really well with the panel resolution of 2560x1440 @ 25.4"( very sharp )
AG coating way better than P2415Q ( my opinion ) ( by far best AG coating I've experienced )
side by side the P2415Q seems "dirty"
My unit has excellent uniformity
Display seems "brighter and clearer" than P2415Q after both calibrated to same luminance. Even thought the retina effect is awesome, clarity and better AG coating made me want to use U2515H more than P2415Q @ 2560x1440 resolution.
Great real estate for coding etc, also nice for web work as graphics/images are not retina scaled.
Great for VMs or boot camp as again no scaling is performed for windows or linux.
No issues with waking from sleep, etc.
Not trying to get in to a debate on better monitor, I just have read lots of people trying to get their older hardware that does not fully support 4k to work and wanted them to be aware of this option. I understand there's no real future proofing with this monitor, but it is a viable intermediate option until 4k fully matures and or replacing of machines that fully support 4k.
It's also worth mentioning BenQ and Asus both have similar monitors coming out with a bit smaller panels ( 23.8 AU Optronics AHVA ) and even smaller pixel pitch .2058.
https://pcmonitors.info/asus/asus-vx24ah-23-8-inch-wqhd-model/
https://pcmonitors.info/benq/benq-bl2420pt-with-23-8-inch-wqhd-screen/
Thanks for this info. I also have a 13" late 2013 rMBP and was tempted with the Dell 4K monitor but concerned about the 52Mhz restriction. This looks a viable alternative. I see the U2715H is also available at 1440p so am tempted with this one as well. Any recommendations for the 25" instead of the 27" I guess the PPI is different anything else?