Not interested in slide toppers. Most of them look terrible after a short period of time and they flap in the wind . We have a trucker spot mirror on an extension pole that we use to look at the top of the slides. Most of the time, we do not have anything to clean off. Our manufacturer did not recommend them or offer them as an option. I think the issue with water on top of the slide toppers is that it eventually causes sagging and the dreaded flapping where you have to bring in your slides to sleep. I have even read where people use straps to stop the flapping. Not worth the aggravation to us. I know we are in the minority