Back when I did vending, I NEVER did BBQ, because I couldn't cook on site, and I didn't want to ask my mentor for cooker time (after all, he had a restaurant to cook for). But, running with 4 square feet of grill, and direct cooking of meats, it was madness. 4 people in a booth was barely able to keep up. It was hot, I got burned a lot, people had to wait anyways, and that was for grilled sticks of meat.
If you want to cook on site, a PBC is just not going to work. Especially for ribs, which take up an unbelievable amount of space for very little meat. Most of the folks I know who vend ribs and chicken are running 84" or 120" cookers, and they are still precooking the larger meats. Vending pulled pork is the easy thing to do.
me: I don't drink anymore
Yelonutz: me either, but, then again, I don't drink any less