I've got both (Pro 10.5 512GB LTE & Air 3 256GB LTE) and neither have a white spot. *knock on wood*
I consider myself a pretty heavy user (time-wise). I primarily read dark text on light background in dimly lit rooms. Because of that, brightness is usually 15% or lower (often 0% with Reduce White Point at 60-80%) so maybe that reduces my chances of encountering the issue.