I think I have said this previously, the quality of the screen depends a lot on psycological/physiological differences between people.

I have a co-worker who cannot use amoled screens, whether pentile or RGB. He said of my previous E7 thet it strained his eyes and N9 is even worse, he claims that the colours flicker so bad it causes physical dicomfort.

For myself, I have no such problems, I find N9 screen easy to use and having nice, even colours.

I think there is similar thing with video projectors using DLP technology, some people claim that they see distracting rainbow effect on the device and others do not see that.