Dynamat Extreme is a great product, for improving the audio acoustics & deadening the sound of sheet metal in automobile interiors as well as blocking road noise, I have been using it for years in my vehicles when I upgrade the audio systems. The biggest drawback to using it on a Harley fairing is the added weight that it will contribute especially when your adding bigger heavier speakers, bigger amps and possibly some add on modules Xm, Ipod, Comm module ect. I would look to use a thinner grade of dynamat it's available in different grades for a little less money. Or as Fired00d mentioned using the J&M Product no matter how much we spend and how loud and clean you like your tunes It's still only a plastic non sealed motorcycle fairing & not a 1 cubic ft acoustically sealed speaker box. On just the inner and outer door panels of my Toyota Solara the Dynamat Extreme adds about 20 pounds of weight to each door!!!
BostonBoy