Every time I have cooked by temperature I have gotten in trouble. There is too much variation between smokers and the dreaded stall can result in the same type of meats having varying cook times. I know many here have enough experience that they cook by tenderness. But for some of us newer people I find that cooking by temperature is the "safe way". I use a target temperature of 180 degrees for brisket and near 200 degrees for pulled pork. I know this does not help if you are trying to schedule your meat to be ready at a certain time. But my strategy is start with plenty of time and have the cooler ready in case the meat is done early. In general, the target time I use is about 1.5 hours per pound but I only use that to try to make sure I have allowed enough time. Using the time I expect to start serving as a starting point, I usually start about 1.5-2 hours earlier than that calculation would indicate I should and put the meat in the cooler to take up any slack. I generally let folks know that dinner will be served in a target range that is about an hour wide to buy additional time in case the stall is very slow or weather conditions slow the cook time. If you have an insulated smoker such as a Backwoods or Pitmaster, weather conditions will not affect cook times as much.
Backwoods Fatboy, CharBroil Bandera, CharBroil Big Red, Red Thermapen, Maverick ET-732