First, thanks guys. You convinced me to go NEC.
Thanks, might have to be the Asus. I don't really want to spend more than about £500 UK price.
I had an Asus PA246Q. The predecessor model to the PA249Q. Only had 98% AdobeRGB coverage instead of 99%. (Be wary of the PA248Q. It's not wide gamut.)
I loved it, although haven't had an NEC or Eizo before so can't speak to those. It solved many, many problems with consumer level monitors.
That all being said, when it died, I counted on the advance replacement warranty Asus advertised when I bought it. Only to find out that they wouldn't send out anything because the PA246Q was discontinued. Pressed really hard for a PA249Q as an equal-or-better model, and they absolutely refused, even telling me the advance replacement isn't really meant to extend the whole period of the warranty, even though their fine print never says that. They seemed like they couldn't care less that my business relies upon this, and that mailing it back for them to fix it and being without it for a month would cause a huge problem.
So, IMO... Have a backup, don't go with Asus, or know you're taking the risk.