Downside is that USAir is the second place player at PHX. WN owns it.
Don't let facts get in the way of a good spin!
Nov, 2010 - Oct 2011 the latest BTS stats available Phoenix Sky Harbor summary of US only Flights
Passenger Counts
US Airways 38.13%
SWA 32.69%
Mesa 7.93% (which is almost exclusively US Express)
Delta 6.19%
AA 3.14%
Other 11.64%
So factor in Express, Mexico and Canada and us has almost 50% to luvs 32%.