I´m running 265/40-20 Goodyear Eagle F1(10 parallel spoke design from the 2010 A8) and noise is no issue what so ever... and I like the quiet'ness of the A8(I seldom crack open a window as I find the noise of the wind annoying
)
But the diameter of the wheel is bigger than the standard fitted wheels, so I guess the extra hight of the tire might have something to say aswell?
Cheers, Jake