🟦 Perfect - Dell U2715H. Basic, boring, stable. At least for my eyes. Only 60hz, but full 8-bit with no monitor-based FRC at all.
🟩 Safe – Various LG monitors including LG 27GQ40W (1080p, 165hz) and LG 27G610A (1440p, 200hz). Both true 8-bit with no monitor-based FRC, but you have to disable all the dynamic lighting and dynamic framerate features. I find these better for gaming than the Dell, but not as good for still images.
🟥 Very Bad – surprisingly the ASUS VP32aq causes me instant strain. Supposedly it's quite good and stable, or at least the 27" model is supposed to be, but I turned this off very quickly after trying it out and have listed it for sale.
(Not sure why my color boxes are so big, I cut and pasted yours… anyone want to tell me the trick to make them look right?)