I can see why a supplier makes the client pay for the return of an item that is deemed defective by the purchaser, but once returned a supplier should then recheck that item and send a refund with the replacement. Most suppliers that I used to deal with (in Australia) honored that return policy, it is a sound goodwill practice that ensures repeat business. Any product can have a faulty component, yes it should have been picked up when assembled but these things slip through sometimes unfortunately.