Well I got a really good run in yesterday and it was my first chance to give the GPS a run through. Shelf works great. Placement is in a great position as I can quickly look down and still have a good view ahead. XM worked great only dropping out under some high mountains on Rt340 leaving Harpers Ferry.
However I was extremely disappointed in the FM Transmitter. To put it nicely, it sucks. I bought a Walkman radio, set it to a clear channel and the GPS too, and even though the radio is about 4 feet from the GPS, it is horrible. If you set the radio to Local, you can't even get a signal, and DX it still has static. I was able to hear it but it wasn't great. Will probably hardwire a headphone cable to plug directly into the GPS.
There is some vibration in the shelf, but I didn't have any issues with it. I may try and build a center support and brace above/behind the instrument panel, but haven't decided if I will do this yet.
Red 2006 V-Strom 650: "the most shockingly competent machine in the world today"
Alpenkönig (a.k.a. King of the Alps): 2005, 2006
1989 Sportster Bobber Hardtail
1990 Electra Glide with Cop Bags