[Daox]

I agree most people won't like having to replace screens with storm windows every season. Its really too bad too considering the major impact these items can have on heat loss.

Insulating blinds are a great way to go too. In your experience, how tight does it have to be to add a reasonable amount of insulation? I have double honeycomb type blinds, but the gaps on the sides are too large to provide any real substantial insulation value. I've thought about adding some type of spacers on the sides of the window sills to lessen this gap.

I don't think condensation will be a problem with these storms. The problem with condensation is that you have a cold piece of glass against warm moist air. With the storm windows, the difference in temperature between the multiple pockets of air should make sure that the plastic layers don't get cold enough to condense water. However, I'll still be watching for it once I do install them.