Well guys, I live in Canada, and it gets dang nasty here over the winter. I don't have the luxury of a free garage, so I keep my car under a store-bought cover, and then in turn under a poly tarp. Admittedly, I needn't worry about mice, but the moisture is of great concern with the constant melting and freezing of our winters. I am happy to say, that with this setup, the car remains completely dry, and no condensation occurs. I was innitially advised to stay away from a poly tarp, but the water got through the cover and I needed wextra armor. Instead, I DO use the tarp, but I keep it spaced from the cloth cover by using some chunks of wood. And no, it doesn't scratch it. The worst that happened over winter was a tree pruner who dropped some sort of sharp object on the car removing a 1 cm slit of paint from the drivers side fender. That made me mad, yeah, but no rust to report!