hello Tony,
I've been enjoying my S4 as well and would recommend it. I can't tell it is not loud, (one thing that can be eliminated with a pair of earplugs), but I assure you it won't give you a pain in the neck, nor will it react strange due to the peak even in high cruising speed. I tried it on a long trip at speed around 100-110 mph and i was so satisfied. As Fran mentioned, it leads the air through the peak all the way to the back of the lid. Last but not least... amazing visibility and killer looks! Go for it mate! Worths every penny.

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