I've thought a lot about this. Considering the additional costs involved and the inability to drive one's own Porsche hard and fast for the first 2k, it's a bad deal.
Taking a Trefffin driving vacation and reserving a 07S or Cayenne S or even a Turbo is more feisable and will be loads more fun:
http://www.fastlanetravel.com
Now if I was buying a BMW or Mercedes brand new, it would be a different deal altogether!