Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
I read reviews on Amazon that this monitor sometimes has issues with wake/sleep. Do you ever have any issues waking your rmbp up with the monitor?
It has happened a couple of times but it was when I was running Windows in Bootcamp. It hasn't happened while on OSX.
 
I like HP's IPS displays so I've stuck with them over the years, they've served me very well in a professional wedding photography editing workstation.

I'm using a 30" IPS display (HP z30i) with my Mac Mini desktop machine... its' 2560x1600 pixels are running at native resolution and it looks stunning. I upgraded from a 24" IPS display (the HP 2475w monitor) which is now connected to my MacBook Pro retina laptop.
 
Just posting an update that I've acquired the second p2715q 4k monitor and am running both of them at 60hz with no problems from a 13" early 2015 rMBP
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.