"if driven properly Quattro handles just the same as an EVO"
I have to disagree, if you watched those videos carefully you'll notice that the S5 went around every corner sideways, he always lifted, makes me wonder
Look at the EVO taking those corners, you will see how differently he takes the corners with both cars.
And in that Topgear video you can clearly see that the S4 under steering, in the dry, when its not sideways around corners.
There are plenty more videos were Jeremy talks about how Quattro tends to understeer, and a video of Tiff nedle reviewing the R8 were he mentions that unlike previous Audis the R8 doesn't understeer on the limits, it actually oversteers. Watch them.