I think it depends on your goal. If your goal is first class upgrades in addition to free flights, try Continental One-Pass. As soon as you make SILVER with them, you get all the upgrades you want, free.

If you are going SFO or LAX to MIA, it is just as easy to connect in Houston as it is at DFW.

Continental also hubs in Newark (EWR) so you can get direct flights there, if that works for you.

You can also earn miles on Northwest, America West and Alaska.

The downside is that if you need to go SFO or LAX to DFW a lot, there isn't a direct flight.



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Mark Robinson