Fixing a cloudy or scratched AGV S4 Helmet Visor

I have two AGV S4 helmets which I bought because they have a great 5* crash rating, (which is safe) but after a few cleans with water, soft cloth and soap, I couldn’t see out the visor (which is not safe).  Then I found some other reports of this online and an acknowledgement (via MCN interview) that there was a problem with the anti-fog coating.  I bought a replacement from Bob Heath Visors, which I have now had for a year and it is fantastic.  Problem solved, no fogging and the visor is easy to clean.