Did a 9.75 lb butt a few days ago, and it was awesome!
I was a little hurried on time, so I kept the WSM at approx 300f @ the grate.
I used a whole basket of Royal Oak Lump. Put about 1/3 of a Weber chimney to get it started.
I used 2 fist-sized hickory chunks for smoke.
Rub was kosher...