Just installed my One XL along with a 12 volt outlet. Mounted the One XL with a mount I purchased off eBay for handle bar mounts and just made a spacer to work on my fairing stay.
Have yet to ride with it but I think it'll work good.
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount002.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount003.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount006.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount004.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount005.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount010.jpg
Have yet to ride with it but I think it'll work good.
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount002.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount003.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount006.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount004.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount005.jpg
http://i170.photobucket.com/albums/u269/l_baumer/GPS Mount/GPSMount010.jpg