Yes, I've had one on the BMW for a couple of years. Very well made, waterproof, easy to take off, leaving the mount on the bike. The only possible difficulty is getting it mounted on the narrow TW tank behind the gas cap. It does look a trifle big on the TW. I routed a cable into it from the front, just used a soldering iron to melt a hole then sealed it with RTV. I run my Ipod off that. the Montana is hard wired with a rugged mount.
Worth the money IMHO.