I would 100% NOT use it for your doors. I used it on my first setup which was a super cheap budget build. Whole setup cost 300 bucks.
I put it on the trunk lid, obviously I didnt smell it since it was basically "outside."
It def helped with rattle but you need a heat gun to apply it or else it falls off. I know this b/c mine started falling off.
Moral: Only use it on ur trunk if you are RLY tight on cash, and use a heat gun. If you can afford better, use better. There are a lot of cheap car audio specific sound deadeners out there.