We had French plastic in our cabin side ports for 20 years, and eventually replaced it with Perspex in the UK 2 years ago, because the original Altuglas was scratched and showing some of the visual apparent cracking.
At first the improvement in clarity was good, but within 2 years it is cloudy. Inside has a smeared film we cannot get rid of. The UK supplier insisted we use ONLY soap and water to clean, but it does not work well.
Outside seems to have micro scratched, although there has been no abrasion that we know of.

What to clean inside with? Windex?
How to deal with scratches outside? Will fine auto paint finishing paste do well? What to Helicopter pilots use (I have seen them polish the bubbles )