The OP said specifically he wanted to cook a couple hundred chicken halves at a time. So the first question is, "what is the square inch requirement for that many chickens?" That may eliminate some of the smaller traditional offset pits right off the bat. Jambo (and my recent discovery of R&O) pits are the Rolls Royce of smokers, but aren't big enough for catering.
I'm going to take a wag and estimate it would take 8000 sq. inches or more to hold 200 chicken halves. That's a smoker 8' long by 3' in diameter with three racks. I could be WAAAAAAY off, so somebody who is an actual caterer please chime in on what it would take.
Here is my next question for the guys with reverse flow pits... Chicken would/should be cooked between 275-350 to keep the skin from turning to rubber, right? Do the reverse flow pits get to those higher temps easily enough?
Large BGE - WSM - Small Charbroil Offset - Weber Performer