One day I went to a car wash where the truck stays still and the mechanism moves back and forth to clean the vehicle. There was a trace of water but that's all.
No issues. Had a similar one on my Colorado and it held up really good after 2 years. When i did get a detail on the truck every few months, id have the guy put protectant all over the cover, the same as they use inside for the leather and it looked like new when i sold the truck. i do wash my truck no less than once a week. unlimited plans are amazing