27" monitor suggestions, please

One of my monitors has died. I've become totally dependent on having two monitors, so I would like to buy 2 new, matching monitors.

I have a NVIDIA GeForce GTX 650 Ti BOOST.
http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-650…
Display Support:
Digital Resolution 4096x2160 Maximum
VGA Resolution 2048x1536 Maximum
HDCP Yes
HDMI3 Yes
Multi Monitor 4 Displays
One Dual Link DVI-I, One Dual Link DVI-D, One HDMI, One DisplayPortStandard Display Connectors
InternalAudio Input for HDMI

I do lots of photo and movie editing, so I'd like 2 good monitors.

I would have a budget of ~$400 for each.

Many thanks

:)

Margaet