Bill, I've had the same problem. Admiral would love to insure my Prodrive STI, I told them it wasn't yet and was just a standard STI, but I would have PPP fitted. They then got their knickers in a twist and started asking me if I was uprating the brakes ! I said that they sell it like that, straight from Subaru, made no difference, the shutters came right down !! On a plus I can get my standard STI for £700 !!
Best so far for PPP £1300 Tesco.........serisously thinking of not bothering at all now.