Very important. It gets rid of all the contaminants so you have a nice smooth surface to start from for example tar tree sap all that lot, and you will find that if it hasn't been done for a while the colour changes back to how it left showroom.
I work for Motorpoint derby and in that case we would refund your dipper. Can't u just tell them to hold it for a couple of weeks with the deposit they have while you sell yours then everyone is happy...or part ex???