Never had a problem with scratching it with fresh water washing, Pledge & an old t-shirt to dry it. Our biggest mistake was not to have any covers until we replaced them 12 years later! When we had the Stratoglass replaced in 2013 the sun had done it's damage. You could push on an area and it would crack but it was still pretty clear. I think not covering them does more damage than anything we could use on them.

We decided when having covers made (12 years to late), we had them made so they were from the overhanging bimini to the coaming never touching the plastic. It worked really well other than looking funny. With our bimini overhanging the dodger we could leave the cover off and have a clear view while in a rainstorm. If I put covers directly on the Stratoglass we couldn't see.