Just got a new Pit Barrel Cooker http://www.pitbarrelcooker.com/ and am about to start my first smoke on it with a 9.5lb pork butt. Used mustard as a rubbing agent and went with Pit Barrel Cooker's recommended rub called Beef & Game Rub http://www.pitbarrelcooker.com/product/4-7-oz-beef-and-game-pit-rub/.
This unit cooks a little hotter and faster than I am use to and uses charcoal as the main source of fuel (although you can add wood chips of your choice for flavor). They claim a pork butt of this size will be done it about 6 hours. Excited to see the results!
Here are the initial pics, i'll post more along the way!