I just purchased the Perfect Flame 36" smoker from Lowe's, I believe it is also called BBQ Grillware. My question pertains to the lower vents. In reading Jeff's Guide to the GOSM smoker, which is just like this one really, he suggest closing the bottom to vents (they don't full close by design). Do you do that for the most efficient smoke? I've noticed that I can open or close them and it doesn't effect the temp much at all. Just wondering how other people set theirs. Thanks!