Cold Storage - Car cover or not?

[Chateau Slate 66]

I'm sure this subject has come up before but I could not find what I was looking for when I did a search.

I will be storing my car indoors, unheated (Minnesota) for the winter and I was wondering if it is best to cover it or leave it uncovered. I am concerned after reading on the net about moisture build up even with covers that say they are "breathable". Critters are not a concern and I can't spend the money for the air dome covers.

Thanks for your suggestions!