Not that someone using the monitor purely for photography necessarily needs a perfect sRGB emulation mode if they intend to use only color-managed programs and browsers and just keep it in wide gamut mode, but if you also want to use sRGB mode for IE or Chrome browsing or for TV or games or to view sRGB images with least banding, etc. here are some measurements showing how the internal adjustments let a NEC PA get sRGB down very well:
perfect saturation tracking curves and hue curves along saturation curves:

perfect primary luminance tracking curves:

perfect alignment and coverage of sRGB max saturation gamut slice:

the primary numerical values, perfect as also shown on the chart above:

excellent TRC tracking on brightest few values:

excellent color-temp tracking until below 10% (the probe doesn't read well there down below 15% anyway):

and the above in numerical form:

a pretty solid automatic instant self-calibration to gamma 2.2 (for movies and tv):

this one shows how the actual sRGB TRC looks (it is NOT a straight line at gamma 2.2) so sRGB images viewed in non-managed programs such as IE and Chrome make things look correct and not with overly-darkened shadows and altered highlight curve:

the very darkest few tones are a touch too dark but most monitor's do not get this perfect either:
