I have the exterior car cover made by Porsche. I only use it in the garage when the car won't be driven for extended periods of time. It is a tight fit and I would not use it with a dirty car. Car covers extend to the wheels and pick up all kinds of debris that can scratch the car as the cover is moved. It's over kill to use a cover on a daily basis and any small scratches you end up getting you'll kick yourself for because you'll blame it on the car cover regardless of what caused them. I'd sooner hang boat bumpers out my windows to protect the doors from careless people who park next to me! Now that would be a sight. Don't worry about the sun. Use a good covertible top protectant, wax the car periodically, use an interior windshield cover and you will be fine. Remember the little ding and scratch here and there and sligthly faded top make it your very personal Porsche like none other. It's like getting wrinkles as you age.
