I bought my first car cover from Beverly Hills Motoring Accessories in California in 1969, for my 1969 Camaro SS/RS Pace Car, and I have used car covers on a variety of cars since then, and currently have a Weathershield type cover on the kid's '97 BMW 540i that sits outside.
Where I used to live for 35 years in Northern California, I had covers for every car we owned and we had many. I believe in California where its so sunny, you would want a car cover to help cut down on UV, heat, and dirt, so that your freshly detailed _____________ (fill in the blank) would be nice and clean and cooler, every day.
I really like not having to wash my car often because it stays so clean when its covered outside wherever I go, so I will always be a fan of car covers, and can take one off and put one on in probably less than 2 minutes.
Windy conditions can cause problems for some poorly designed covers, but the newer designs now are coming out with more ways to attach it more tightly, so that wind doesnt get underneath it as much.
Of course, the best designed covers will fit every vehicle perfectly, tightly, and have the best possible grade of elastic in the front and back seams, so that it stays on very tight year after year, is easy to wash, and small enought to be rolled up into a small, supplied cotton/canvas bag, that is easily stored into the trunk/boot of any vehicle.
The grommets should always be covered in a padded fabric on each side, and a quality, cut proof cable and lock should be supplied with each cover, and not be an option to buy..
I dont really care for all the fancy colors, as it draws more attention to your vehicle, and that may or may not be a good thing in some areas of the country.
I prefer just gray or light blue; something that blends in easy with normal outdoor colors.
Up here in the Northwest, I have been really recommending to my Clients to get covers, especially if their vehicle/s are outside, to help prevent the onslaught of all kinds of fungi,moss, compost, etc., that gets into every seam and starts to grow little trees, multiply, etc.., if it stays there too long without being removed.
Dan F