When I sold my Kawasaki Versys last year (to buy a bike with lower rear footrests in the future - the K1300GT as it turned out) I sold to the Superbike Factory. The supplying Kawasaki dealer was not buying bikes for stock due to the large volume of part - exchanges due in with the forthcoming registration change, and suggested that I contact the Superbike Factory as he had heard good reports of them.
In all, they were very impressive, offering a price that almost reached the part - exchange value, collecting promptly and paying in full at the time. They sold the bike very quickly for a modest profit.
The whole deal went very well, I was able to sell for a fair price, go off to Japan for our regular visit and, on my return look for a suitable replacement bike at the end of the season when prices dropped.