Gary is great to deal with. I have an older version of the Ampli-Rider installed on another bike that I've been using for probably 10 years to mix signals from GPS, radar, and music (either MP3 player or Sirius). Mine has the remote volume control hardwired on both ends. It works well, though I do get some whine/noise that I believe is caused by the GPS, despite adding a noise filter. Some years ago the unit stopped working, so I emailed Gary about it. He had me send it to him, whereupon he fixed it and sent it right back with terrific communications.
I originally had the volume control mounted in a dash fairing that I drilled a small hole through just so the threaded part under the knob stuck through and then was held in place by the retaining nut on top (with the knob in place above that). Worked well and was a clean/neat install. I later moved it to just underneath the left switch pod and attached it with two-way tape for automotive applications. I love it there as the knob extends out just enough that I can use my index finger to easily raise/lower the volume without ever taking my hand off the grip or eyes off the road.
Good product and good maker/seller.