BD nailed it, I usually cook briskets at 250 for the first two hours if I need a pretty smoke ring then ramp to 300 or 325. Plenty of H&F brisket threads on here.
You do what you have to do, so you can do what you want to do!
Ole Hickory Ultra Que 2
18" Weber OTS
Primo Oval XL
NB American Gourmet offset smoker
Big Chief Smoker