8.2 and I like a couple others got the first complimetary thing the opposite way around having no clue what it really wanted.
My guess is, to a large degree, the better the screen the MUCH easier the test is, I wouldn't be surprised to find people with 9+ have a S-IPS/MVA are one of the much newer TN's and well well calibrated. Better screen, better difference between the colours, the obviously easier it is to pinpoint the best answer while on a screen with worse colour recreation and smaller range of colours it will be much harder.