I have used Rain X on my Nolan visors without any problems it worked extremely well inside and out, BUT when used on My system 4 the visor was history!! BUT after reading one of your earlier replies I have to conceed that I applied it to the interior and exterior of the visor. Would I risk ruining another visor to see if it was because I applied it to the inside, Well no I wouldn't. Maybe I will try the pledge suggestion as it seems to have been tried  and proven.Steve.