I've had my corian for over 15 years, I clearly remember the installer said to use an ammonia based cleaner. So I use windex mostly for the bathroom countertops, for the bathroom and kitchen sinks I have always used soft-scrub. The kitchen countertops I just use soapy water. It's pretty resilient. Just never use nail polish remover around it. The acetone will ruin it. My 17 yo DD. Knows to never use nail polish or remover around it.