Sounds Very Good Eric, Pork Butt is pretty hard to screw up if you can keep your temp low, like between 225 and 275. I usually shoot for a target of between 250 and 275.
The Pork butt is sliceable at an internal temp of 180-190 degrees and is pullable at 195 and above. I like to pull mine between 195 and 200 degrees.
Also, the during the cooking process the pork butt will reach a plateau temp somewhere usually around 150 to 170 degrees. It is also not uncommon for the internal temp of the meat to drop for awhile too. Don't worry, it is not your smoker loosing temp.
During this temperature plateau, (which can last for several hours), all of the collegen and connective tissue is breaking down. It is rendering it from being very tough to very soft .
Also, when you pull the porkbutts from the smoker, it is advised to wrap them in foil and let them rest for at least a 1/2 hour before serving. This allows the juices in the meat to redistribute back through the pork butt.
It can sometimes be hard to judge how long these smoke for as it is all done based on internal temperatures. I have had some pork butts cook as fast as 11 hours, while some have cooked 22 hours. However, I usually plan 16 to 18 hours for a pork butt cook. It can be a long time when its cooked low and slow, but they do turn out very well.
Finally, if the Pork Butts are done early than expected you can always keep them wrapped in the resting foil, wrap them in a towel and place them in a cooler with no ice. They will stay warm for a few hours that way.
I am actually gonna be doing some Pork Butts myself this weekend. My neighbors are having a family reunion and asked If I would smoke some for there party. I will likely start with 25 to 30 lbs of bone-in pork butts, which will cook down to 15 to 20 lbs of pulled Pork (You loose alot of volume during the cooking process).
Good Luck on your new smoker....I love cooking on my smoker It is one of my favorite tools.
smoked a pork roast yesterday and some veggies, they all turned out real good. I am going to have to learn how much charcoal to use and how to keep the temp up but it was just darn yummy. and my best friend was watching for stuff to hit the floor