There is quite a bit of adjustment with these fairings, you've got up and down, depending on where you place your fork clamps, and there is an in and out vertical adjustment on the "buttons" that attach to the clamps.
It will take a few times of adjusting but even when I had the 5" shield, I had little buffeting at highway speeds. I have recently went with a "long ride shields" brand 8" dark smoke with the flip at the top, and it's nearly buffet-less.
'09 Kingpin 8Ball
'06 HD Road King
'06 Vulcan 900 Classic