I recently bought a pair of pink kiss GHD's from ebay and the seller had 98% positive feedback so I stupidly thought that they would be fine. When they arrived I tried to register with GHD only to be told that the straightners were counterfeit, I automatically contacted the seller who assured me that they were not copies and the reason that GHD could not register them is because they are straightners that have either been returned to GHD as being faulty or old stock. What a load of rubbish. The seller then continued to insult me by offering me a refund less the cost of postage, when I told her that I had paid with paypal and would take it further she backed down and I have now had a full refund. I have today noticed that she has left me positive feedback as a buyer, obviously hoping that I wont report her for selling counterfeit goods.
I have ended up buying a pair from Amazon which were only £20 more but I now have the peace of mind that I have a valid warranty and that my hair is not going to fry as they possibly could have done with the dodgy ones.
My advise is be sensible, dont waste time searching endlessly and waiting for auctions to end and pay the bit extra and buy them from a pukka company who is registered with GHD.