I have flown Southwest, Delta, AA, TWA, America West, and United (I think). By far, the best Ontime service is Southwest. best service is..Southwest, Cheapest...Southwest. Obviously Southwest is my favorite Airline I fly, and I try to Fly it all the time, if Southwest operates to where I want to go. Delta is #2, AA/TWA #3, United #4 and last..America West #5. America West had severe turbelence everytime I flew them, and their service was horrible. Over all, Southwest!!!