http://jekillandhyde.com/US/
I Have them under my SG15with the stage 1 screaming eagle airflow kit. You cab also choose the button that can gradually open and close the valves so you can choose the sound level yourself. The Sound is great an deep. Deeper than the screaming eagles an les loud than the open big shots of VH. I'm very pleased with these pipes. In The Netherlands you can get fined for pipes that are too loud, and than you have to redo it to stock or CE certified standards. These JH are CE certified. In closed position the sound is dull. when open it is a blast and the real Harley Sound.
Just to be clear, stage 1 is a free flowing exhaust AND a high flow A/C, along with an appropriate tune. Doing the pipes alone provides only a negligible performance gain. The normal purpose of installing a free flowing exhaust, other than being louder, is to handle the extra volume of air moving through the motor due to the addition of a high flow A/C. Without increasing the incoming air volume, your perceived performance increase by doing pipes alone will be mostly psychological.