Hi, purchased this a week ago (yeah, I know). 

Anyway, on more solid coloured pictures such as a sky there are slightly dark patches in all four corners of the screen. About an inch square so not terrible, but slightly annoying. 

Being back lit as opposed to the 55" edge lit I was sort of assuming that there wouldn't be this vignetting issue.

On a complicated moving picture you can't really see them, but they do show up on block colours like kids animations. 

What I'm really asking.. does anyone else have a 65" 8509 and do you have slightly dark corners? 

Cheers,

     Brian (oh... the rest of it, including Android has been just fine....)