SAN -- Simple 5 minutes taxi you are downtown and if you are Elite, security line isn't a problem.

SFO--- BART enough said

STL--- Metro into downtown

MSP -- You can take the bus or transit from the airport to Mall of America in less then 20 minutes.

Austin* -- Not bad if you can get in early and avoid the parking lot call I-35 and a later flight to avoid I-35 But normally its a 10 minute taxi ride to 6th St from the airport.

PHX-- Again 10 minute taxi drive to downtown or 20 minute drive to Scottsdale.

The more advanced airport like ORD can be a challenage but if you know ORD and Chitown then its not a problem.

But then again MR's usually don't leave much time to go into the city..