So I've just bought one of these:
https://www.dell.com/en-uk/shop/dell...or-accessories
Key specs that I was after are:
-27"
-1440p
-165hz
-1.07 billion colours
-98% DCI-P3 coverage (claimed)
-'Fast-IPS'
-Freesync
so this seems to fit the bill. But let me warn you from the start:
DO NOT BUY THIS IF YOU ARE SENSITIVE TO IPS-GLOW
But more on that later. First the good:
Desktop
Once set up (don't ask, freesync seems to be a dark art) this is a lovely monitor for motion. Going from 60hz to 165hz is a revelation, even on the desktop. Everything is much nicer - I found myself scrolling webpages for fun, it's much smoother and clearer. I hadn't noticed how much my old screen was blurring in motion, but I couldn't go back now.
Games
Games are likewise better with freesync. I'm on a GTX 1060 so was 60fps with vsync on at 1080p before. Going up to 1440p has knocked my framerate down to 45-55 for the most part at the same settings in games like Forza Horizon 4. While this isn't quite as fluid looking as at 60fps there is no screen tearing and it's still very smooth with none of the noticeable drop in frame rate if the odd frame takes longer like before. On the other side, firing up games like Destiny 2, Skyrim that can output high frame rates show they look buttery smooth.
Photo editing
Colours were pretty good out of the box, but I calibrated it anyway. I measure DCI-P3 gamut coverage as 96% rather than the claimed 98%, but this is still plenty, allowing for more vivid reds and greens especially compared to my previous monitor (which was 98% of the smaller sRGB space). It's proving useful when dealing with high bit colour photographs that have subtle colour graduations.
That IPS-glow
My previous monitor (Dell U2311H) was also IPS, but it seems this generation of 'fast-IPS' displays is far worse in the IPS-glow respect - compounded by screen size which make the viewing angle worse unless you put the display further back.
How bad is the problem? For desktop use, not at all, nor while playing any game that displays any colour other than black. But if you mostly play space games or watch sci-fi films then strongly consider how much you want a perfect image. It basically acts as if you've got a very slight white reflection in the bottom edge/corners - if you've had a light on in the car while driving at night it a bit like that. It's not distracting, but it reduces contrast and means you can't see detail in blacks without moving your head to look exactly perpendicular to the spot. Combine that with black levels that are not especially low anyway across the whole screen and it's enough for me to recommend a VA or TN display if space is your main thing. I'll go back to watching films on the plasma TV (sorry planet). Still waiting for OLED I guess.
IPS glow is not considered a fault by Dell, it's a characteristic of this kind of display.
Other stuff
The screen looks very smart. There's a LED light rail at the back which I quickly turned off and will never mention again. Bezels are narrow apart from the bottom (though the screen stops a good 6-7mm short of the edge of the glass on the top three sides). It comes with cables and a USB extender. There are cable tracks/holes for neat routing. The stand has a great range of adjustability and a pretty small/neat base footprint. Controlling the monitor menu is a slightly flimsy joystick which you also press in to select items, but it's more intuitive than having vertically placed buttons for horizontal actions.