I've only used it twice and it's worked great both times. I had the same concern and asked someone else the same question. I only used the thinner stuff because that's what I had but if had a choice I would go thicker. The thin tank was a pain in the butt to work with when fitting the door. Had to put a lot of stiffener supports on it. I love my smoker but I'm glad it's complete. Next one will definitely be thicker. You close to KY cause I'll sell you mine. Lol. Too big for me so I'm gonna build a smaller one. Good luck on your build.