They both work great. It depends on what you want. Brine em first and they'll be nice and juicy. 1 cup of sea salt and 1 gallon of water add garlic powder, onion powder and other spices if you wish. Over night is best but as little as a few hours will do.
Whole chickens about 2.5 to 3 lbs take 3 to 4 hours at 250 degrees
Whole chickens about 3.5 to 4 lbs take 3 to 5 hours at 250 degrees
1/4s take about 3 hours at 250 degrees
Make sure to cook to an internal temperature of 170 degrees.
Spray every hour or so with apple juice if you want to add BBQ sauce do it the last 30 minutes.