I bought the monitor before finding this post and it arrived today.
So far so good, but it will take a bit of getting used to and playing around to get it just right. I have a 27" Acer XB270H which a great TN screen but wanted a bit a bigger screen, and an AOC 27" IPS, not sure of the model. It was a panic PC World buy after my monitor died.
Initially, I could not run it at 144Hz with the Display Port cable I was using on the Acer at 144Hz with no issue, not without lots of flickering (fine at 60Hz)and after reading over some of the posts I thought it would be a dreaded RMA
However, after changing the cable for the one which came with the monitor (I had two in the box) it worked fine, so bonus!
I've only played Guild Wars 2 and X4 Foundations so far and I can't complain, it doesn't have the depth (best word I can come up with) of the Acer but I've not noticed any ghosting, flicker or artefacts.
The only downside with the change, which has nothing to do with the monitor, is my work laptop can only support 1920 x 1080 so it doesn't look great, but that just for work so who cares.
Thanks to all who have helped out on the post, some great pointers which I hope will help me get the most out of the monitor.
Matt