Well, it's below freezing where I live now, and I need to help my sister get her keys out of her jeep tomorrow morning (she locked herself out haha), so I can let you know tomorrow lol Probably gonna have to wrench one of her side windows out. Just hope we don't break one of the plastic clips doing it.Do you notice any difference in shrinkage/ difficulty in raising/ lowering/ installing windows in cooler weather between the 2 materials ? Thanks