I did the front only wrap, along with some extra material at the bottom of the doors, when it was new. A few months later I decided to have the entire car (less the frunk) wrapped. Glad I did as I drove about 5k miles of winter mountain driving this year and am sure the wrap helped a lot.
Having said that I still have about 4 places on the hood where rock chips broke through the Xpel and in one case still chipped the paint. My car still looks as good as the day I got it in March of 2016. Of course parking way out in the boondies doesn't hurt either. Xpel cannot save you from door dings.
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