AA, UA, NWA, USAir, Delta, Southwest - they all suck as far as economy class treatment goes. Shitty seats, dirty cabins, nickel-and-diming you for a bag of chips or box of shitty food. All of the major carriers are pretty bad. The smaller carriers do a slightly better job.
"The fundamental principle of science, the definition almost, is this: the sole test of the validity of any idea is experiment." -- Richard P. Feynman