I usually buy a 2-bone-in standing roast, which usually runs about 4.5 lbs and can feed about 5 people, depending on their appetites and whether or not you serve sides.
Make sure your roast is near room temperature (let it sit out on the counter for an hour or so). I prep just like I do a steak, lots of kosher salt and black pepper, and olive oil. Simple. Sear on all sides over lava coals, rest for 10 minutes or so, then slow cook indirect with drip pan at 250 dome until you get about 130 - 135 F internal temp (this one took about 2.5 hours). I use mesquite wood chunks as well.
