In terms of color differences.. there effectively aren't any. I have had some time to now also test the NEC since the initial review and its gamut is about as good as the Eizo. Therefore the primary differences are resolution, in built calibration device and the more advanced software for soft proofing in the Eizo (see my video in the above review).
NEC software has virtually the same features as EIZO ColorNavigator, but it's divided to separate SpectraView II and MultiProfiler applications - you can apply soft proofing using internal 3DLUT of the display using NEC MultiProfiler and the result will be the same as in ColorNavigator.
There will also be brand new release of NEC SpectraView calibration software soon.
NEC has slightly smaller horizontal resolution, but is noticably larger:
In case of NEC PA322UHD the price difference is even larger, while the hardware is just the same. The SpectraView Reference has +2 years of warranty, hood, and european SpectraView Profiler software (which is worse than US SpectraView II software)