Originally Posted by Djlawman
So, in your case, if you concentrate on the United MileagePlus FF program, you can also take flights on US Air (another Star Alliance member), and use your United FF #, and credit that mileage to your United Account.
...and America West!
Also you get elite qualification miles to United when you fly USAir or America West (and other international carriers).
Try to focus your miles on United so you can get Premier status and Economy Plus access. Out of Dulles, United is the no-brainer choice.
I go to Baltimore from Seattle and drive to Dulles to get the best non-stop options to Seattle. With United you can get many non-stops to SEA, SFO, LAX, PDX on the west coast, and redeyes back if you need em.