Still glassy-eyed from lack of sleep last night waiting on two 9.5 lbs butts I smoked in my MES 30 with the Mailbox mod. I guessed the time to finish to be 11-12 hours, same as a single (prior mailbox mod), but the first one didn't hit 203 degrees until just after 23 hours and the 2nd I let hit 205 degrees after 27 hours! I can't believe the time it took. I pre-heated to 250 and then kept it at a steady average of 235 degrees for the first 8 hours, then kicked it up to an average 255 degrees for the remainder of the time. I only opened the door once within the 24 hour period to visually check and insert a hand held digital thermometer to confer the readings I was getting on my Maverick thermometer. I was using a iGrill thermometer to monitor the inside temp of the MES. I'm wondering if the Mailbox mod has something to do with the seemingly long cook time. Any other suggestions?