I prefer simple treated bbq. I rub with 1 part kosher salt, 1 part course ground pepper, 1/4 part garlic powder, 1/4 part cumin by weight. I have cooked them between 325-350 and let it go nekkid the entire time. I did an 8lb pork butt in 5 hours.
Here is the finished butt, going into some foil for the long 2 hour rest.
When I pulled the pork, I put the fat that gathered in the foil with the meat. I also finished with a light touch of an Eastern Carolina Dip. It is made with Apple Cider Vinegar, turbinado sugar, kosher salt, and crushed red pepper. I add it in a little at a time until you get a hint of the vinegar tang when you bite into the meat. (It should be a subtle note of vinegar and not a strong flavor)