Durham Fox
El Dude Brother.
Why? There's 1000's on auto trader? Its not like anyone couldn't drive past your house with it parked on the drive and read the number plate? If you put your reg into the DVLA website it will tell you what make model and engine your car has, so really anyone could access this information.
Also have you thought about getting one of those after warranties? I know someone who has it on his Saab 93 and pays about £300 a year (less than depreciation on most cars) and that covers most of the stuff that the normal 3 year one does.
I've looked at warranties yes and in general the cost is about as you state. Problem is nobody pays 100% of the claim over a set mileage which to me seems crazy.