Worst.
Houston - If you fly Continental you end up flying through that place and they never have enough seats in the waiting area for the flights, they have these circular hubs at the end of the terminals and have about a third of the seats they actually need so you end up sitting on the floor in the hall until it is close to time for your flight.
Philly - the place is a craphole and security is nearly as bad as Atlanta and even more unorganized.
Atlanta - if you don't have to go through security it isn't nearly as bad but the place is always crowded and gates are always being changed, you need to give yourself at least 2 hours between your connecting flights. Once you board you end up waiting forever to take off because the place is so busy. You can always find a place to eat though, so if you have to go through Atlanta it is probably the best of these airports.
Charlotte - Another craphole airport with poor lighting, US Air/United never seems to make their schedules and the food absolutely sucks in the place.
Miami - Why anyone would want to have a hub in Miami is something I'll never understand, the only thing it is good for is catching flights to the Caribbean and South America, but they use it to fly all over the US and they close the hub in St. Louis. If you end up on one of the American Eagle Embraer jets you have to board a bus that will take you from your plane to the terminal. The food is terrible in the place if you can even find a place that is open after 8pm.
Some of the Best
Minneapolis - Nice new airport, but it is a bit spread out and you can walk forever to catch a connecting flight.
Memphis - It is a Delta hub and not nearly as busy as Atlanta. If you can catch a flight through here it could be a better option than Atlanta. They typically use it for the Delta partners. Don't choose a window seat if your jet is a Canada Regional Jet.
Chicago - Yes it is crowded and can be a bit of a pain to navigate if it is your first time there, but there are plenty of places to eat and it is nice and spacious.
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