Re: Optimal Winter Car Cover?
After living in a city with wintery snow and ice, I would not cover any car to protect it from snow and ice. Most likely the cover will freeze up making it difficult to remove. I have never had a problem with snow/ice on a cars finish; salt is another story.
If you truly want to protect the car from the elements in the winter, you might want to look at a portable garage. They are ugly as h*ll, but they work. A trade name for one of them is Tempo. Basically they are a metal frame covered by a plastic covering. They go up in less than a day and come down just as quickly. They will protect the car from the elements in winter.
I store my 911 in the winter in a heated garage. I cover it with a Porsche breathable car cover. If fits great, breathes and protects the finish from dust.