WT, some folks don't bother with the foil at all. I find that it does make clean up easier. I've always used the heavy duty foil on the bottom pf the smoker and top of wood box and haven't had problems with the foil. Even after multiple smokes the heavy duty foil will come off easily. Yes, the grease will find its way under the foil and the stainless will discoler a bit, but that is to be expected.