We will be taking our Model 3 in for PPF in the next few weeks and plan to have Ceramic Pro applied to the Xpel on the body. We were asked about applying it to the windows/glass and not sure what to think. I can see adding it to the Xpel so that items like bird droppings don't etch it but not sure I'm seeing the benefit for the glass roof and windows. Am I missing something about it?