I sell a lot of transponder keys on Ebay and I have noticed that a lot of dealerships know nothing about the keys.  Lots of times they tell the buyers that the keys will not work at all (They all do)  Im not sure if they know what they are doing and trying to scam people or if they just have no clue when it comes to the transponder system.  So if you purchase a key from Ebay don't get mad a the seller too quickley if the dealership tells  you the key wont work,  contact the seller or a local locksmith to get the problem worked out first.