this is some crazy stuff, I have had 5 total mini 9/a90 and never noticed until I put three of them together side by side. The girlfriends and mine are sharper when the brightness is cranked up. My kids is lighter, like the brightness overpowers the color. It is minimal, but very noticable. The better ones are the AUO, the lighter looking one was an LP. Glad the kid got it, I am surprised it isnt broke yet! LOL. BTW, of the AUO ones we have one was a A90 and one a Mini 9. The kids is a mini 9 as well. Looks like they mix and match whatever is available at the time.