I have a pit boss. It's a pellet one, they make one that's half pellet, half propane, but that's overkill for me. It's a perfect size and get the job done. It has an adjustable dial, in increments of 10 degrees up to 300 then it's 325, 350, 375 and 400. It holds its temperature very well and I'll turn it up to 375 to cook burgers and steaks on and it does a great job.
Brisket was 4.5 pounds and that cooked for about 6 hours.
Pork shoulder, which was by far the best one I've done, was 8 pounds and cooked 9 hours