You will only get 1 car per model per payed download.
The game data on HDD will be altered to store that you have received the content it will then lock the cars from being tradable or rented. You will go to the transport truck to get your cars.
Once the game data on HDD is altered the game will ignore any more store downloads for the same items as they will allready be listed as unlocked on the GT5 installer......
If you delete the Game Data from the HDD you will be allowed to unlock them again as you erase the installer log.
Tracks will unlock automaticly on the HDD after GT5 installs the data token.
Paints and driver gear will be in the same section they have allways been, the items page.
The question will be IF the quantity will have a value or an infinity symbol.