Thanks Briwy!.. I have been using a cheap JK screen cover, with some mods, but during the last few (very windy) nights, I have reverted to the fabric internal window covers that were supplied with my Beach.
These are not, and do not pretend to have, special low condensation skills, and yet I have been impressed to see only a small amount of condensation form by the morning, hence my question about the Brandrup option, maybe with a little extra help from something like this, I may end up with a neat internal solution.
Clearly overnight temperatures have not been that low, so the real test will be in a few weeks when it gets considerably colder.
Has anybody else on here actually tried these, and if so, I would love to hear what you think?
T5WOB, I'm not sure where you were going with your last statement... but thanks for your comments earlier!