Everytime by garage door rises, there sits my 330Ci snug as a bug in a rug under its Evolution car cover. I ordered it this year from Bav Auto. It took about two weeks to get it but it fits like a glove, especially around the mirrors, which kind of look like Mickey Mouse ears, if you know what I mean. If you're looking for a car cover, you should have no hesitation about the quality or the fit of the Evolution.
If you're looking for an indoor only cover, stretch satin covers are hard to beat. Very well lined and fit like a glove. CoverKing covers are available at AutoAnything I have a silver/black one for my 335. This is the Audi R8 satin cover.