These cars are relatively new so I'm not sure where the 'problem spots' are going to be. It took me a couple of cans, but i pulled the underbody felt down, sprayed all under there as well as anything that could get exposed to the salt/brine. Also got the door james, hinges, rear hatch, hood, fuel door, suspension components, etc.
I can deal with the 'dirt' around where it was applied as it's protected from the elements. If it takes care of the car, i can deal with the dirty look.