I have decided to get a Cee Bailey windscreen for my 2010 RT and at 6' I am opting for the +2" taller screen. My question has to do with references to visual "distortion" that I have seen in some discussion of hr Cee Bailey screen. What is this about? Is it due to the up curve at the top of the screen? Or is it something to do with the refractive index of the particular grade of acrylic used in the screen?