My home base is SFO/SJC and frequently go thru ORD, DFW, and STL. Even with the demise of DTW, PHX, etc., belonging tom the AC is an eaasy decision. I really get to hate non-AC departures where I have to stand in line, and then try to find a seat in the "arena". Consider the cost vs. your hourly rate that you are paid: see, it's an eaasy decision...