I road this bus over the holiday's and loved it (though it was packed and I had to stand). It sure beats the walk. BTW, I have made it from F9 to C32 in 8 minutes to catch a flight that the doors were closing on.
The bus is a great idea and I am all for it, as I my home airport is served by express, so I am there all the time.
Thanks UA/UAX Employees!!!!
See ya in the skies!!!