Like jules says, this has been covered before.
My dealer tried to charge me £300 for GAP for a 3 year policy. I went on the net and found a 4 year one for £190. When I went back to the dealer, VW did their policy for £190 just to get my business.
Personally I wouldn't bother with Lifeshine/Supaguard. Waste of money. Buy some Jetseal 109 and some good wax. Much cheaper, much better.