I like the California Car Covers also.
I also purchased one of the car bags. This is made of the same material as a tarp and has a zipper 3/4 of the way around the bottom. You open it up and place the bottom on the garage floor. Then drive the car onto it, install your car cover to keep from possibly scratching the paint, then pull the top of the car bag over the car and zip it up. The reason that I used this is because my cat had access to the garage for her own protection and I did not want her to possibly be exposed to grease, gasoline, antifreeze, etc., plus I did not want her climbing on the car. I no longer have a cat and I've not used the car bag in quite a while. I would like to sell it, and can deliver it to the MARC Meet in Gettysburg. If someone is interested, please contact me. It should fit any Model "A" or similar size car. Might be too small for a "AA".