These things solved our condensation problems completely. We've had a handful of below-zero days and no condensation on any of the windows we bought Indows for. We'll have to take them out come spring and I'm not looking forward to that nor trying to store them safely until next winter. The one thing we didn't like was the delivery. We received emails telling us that the delivery truck would stop at the curb and we were responsible for moving them from the street to the house. I'm almost 80 and couldn't manage that with my wife so I asked my son to take a day off work. Well when the truck arrived the driver used a pallet jack and move the package to our garage without us even asking him to do it. That's bad! The package had some external damage but not the Indows.