I didn't season mine prior to using. I did get smoke leakage from the lid, door and therm but the door and therm sealed by the 3rd cook. The lid still needs to be set on right to minimize leakage. I didn't notice heat issues but it was my first few cooks so I didn't know what was normal or not.
Flip side, once it does get seasoned, watch for flaking on the lid or cylinder. I quick blast with the hose or wire brush if you're more thorough works fine.