My original comment was made bearing in mind that the appropriate insurance had been bought for a test drive. I wouldn't let someone test drive my car without insurance.
As I say I will but I am not keen on it and if I have the slightest doubt about the person or something don't add up the answer would be no.
Because the reality is there are loads of SVR's at Jaguar dealership across the country, so if you want to do test drive, go drive their cars, then when you know its the car for me and you know what to watch, listen for etc. come and passenger ride in mine.