Display resolution is fantastic on the iMac 5K, but gamut is relatively narrow, and what about display quality with all aspects taken into account?
Th iMac 5K screen is shiny and in this regard it is clearly inferior to the NEC EA244UHD and PA302W, which sit a few feet way on my desk. The first thing I noticed about iMac 5K display was my backyard. Meaning the iMac 5K display still has mirror-like qualities.
I rate the 24-inch NEC EA244UHD as equal in general display quality (ditto for the PA302W), but obviously superior in avoiding glare, superior in color gamut, and the NEC displays can be properly calibrated too (iMac cannot be calibrated at all). Its professional-grade sibling, the 32-inch NEC PA322UHD will be reviewed by DIGLLOYD in late Nov/early December.
Bottom line: I love viewing images on the iMac 5K display because of its vast screen real estate (14.7 megapixels), but that is its only real merit over a quality 4K UltraHD display (pixel count). Which is an operational reality but not a criticism of its value—where else can one get a $2494 5K display with a free computer built in?
For professionals with color-calibrated workflows, where color gamut, color accuracy and grayscale tracking over time and temperature matter, screen sheen compared to print media—the iMac 5K can certainly be used, but one need only view it side by side to see that the NEC displays are a better choice.