I had some problems with smears where I hadn't worked it in well enough and had probabaly over-done the application. Windex removed it from the windows with some elbow grease. For anybody who is comtemplating applying, don't over apply and flatly expect to have to clean your paint if you plan to apply to all surfaces that are affected. The biggest 3 killers of weatherstripping that I know of are UV, heat, and movement so even though part of the strip isn't in direct view it's subject to abuse from parts motion and heat.