Dan. Do not trust the Therm. on the unit , trash for the price of the unit , and at the wrong position in the Smoker.
Bass-Pro Shops have small 2" stem therms. for placing at grill level and do fair , just not top qualitybut will do for us poor people. Be sure to get a Probe Therm. for the meat , and I feel Brinkman would be good to start , however save for a Maverick, a good investment.
You are on the right track in watching the temps. Have fun and...