I contacted the seller asking if he had any customer-testimonials because a few of us might be interested in these, but he just gave a rather pathetic answer and an even more pathetic guarantee....
Dear maddogmcq, We have sold many of these, you can check our feedback for customer comments.If you are at all unhappy we do offer refunds for UNUSED items within 14 days.
- sandybikespares
Needless to say, customer comments on eBay are the usual "Arrived quickly thanks" type remarks.