I use autoglym window clean (not the polish) Important to have good quality microfiber cloths. occasionally I use a clean window e-cloth but results are better with the spray. Also don't spray onto the windscreen i.e. on the cloth..
Autoglym Glass Polish ... for the last three or so years, it has additional anti-fogging agents in the mix.
Wash the top of your dash, too, just warm water and a microfibre towel. Do not dress. Crystal clear windows can glare as the sun bounces off the dash - washed, devoid of product, it lessens the reflection.
I'm a bit funny about my windscreen and go mad when swmbo rubs it to clear it. Keep telling her to look through the letterbox bit right at the bottom. But cleaning is just water a bit of vinegar then newspaper and lots of elbow grease.
Thank you very much gents.
Tomorrow morning I'll use some AG fast glass (sprayed onto an ecloth as we don't have any newspaper), and wipe the dash top. I'll use the glass polish at the weekend if needed.