I was a CO Platinum for a number of years. Over the past four, I have been an ExecPlat on AA and for the last two, a United 1K due to travels in Asia (this will be the last year for the combo status). Overall, my vote for frequency of service, customer support on dedicated desks (outstanding with AA, horrible with United having been outsourced to distant lands), and opportunities to use miles for awards (one of the chief reasons I left CO), it would be AA from SAT for anything beyond the adjacent states. For those flights, SW is an excellent alternative.