Mummel, I'm not Bear but I've recently had this discussion with Jted and with Bear. Jted said that at about the 3-hour mark the temp should more or less stabilize (I'm really paraphrasing his words here) and from my personal experience I agree with him. In fact, after that point I've seen the controller remain at the set point--with a few degrees either way--for the rest of the smoke. Remember that I've got a MES 30 Gen 1. Your experience with your smoker may be different, especially if you have a MES 40 and a different generation. But this is what I've observed the past 5 times or so I've smoked.