My dad has one that he got with his scottoiler. He let me use it when I went to Portsmouth and for long dual carriageway stuff etc it was quite useful but in towns it can get in the way. Easy to move it though, you twist it the opposite way to the throttle. I haven't bought one since so I guess I can't have been blown away but it was fairly useful for the majority of that trip and kept my hands and wrists slightly more comfortable.