Last night I decided to smoke my first brisket in the XL BGE. It was sleeting and snowing with a temp of 24 degrees. At 10 PM, the BGE had settled in at 250 and the packer was coated and ready. After placing it on the rack, I stayed up 3 hours and monitored the dome temp. It maintained 250 so I hit the sack. Got up this morning and after a total of 9 hours, the BGE had dropped to 240. I don't have any of the fancy controllers so I was worried when I went to bed.
I am so pleased with this cook. It took the 10 lb packer 10.5 hours to get probe tender. I wrapped in a paper sack and coolered it for a couple of hours and finished off some burnt ends from the point.