That's a LOT of butts! It'll be like pulled-pork-palooza around Don's house! That's definitely a full load in the #2. I would plan for a little more time, if you've never done that much poundage at one time - maybe a couple of hours? Gregg's right about the hold. I've actually gone to 135 when I hold meat, and open the door for a couple of minutes when the butts reach 199. This helps cool the interior of the smoker so they stop cooking. The idea of the "hold" is to keep the meat above the 145-degree "safe" temp until it's ready to serve, but stop the cooking process. I've held large cuts, like butts, as long as 4 or 5 hours with this method, with no effect on moisture/tenderness. But, even if I hold one in the smoker, I still remove about an hour before eating and double-wrap in foil for a rest in the cooler. This allows all those rendered juices to re-absorb into the meat and get really happy. Let us know how long it takes for 4 at a time! Oh, I'd probably up the temp to 240 due to the mass in the smoker.