I agree with Flynavy, 560TT and 125 will get you in the door of about half the regionals. If those are your three choices I'd say PSA, but as most guys will tell you, try to go somewhere where you like the bases. I'd be hard pressed to recommend mesa b/c I've heard the quality of life is horrible but they're definately more west routes then you'd ever get at psa or piedmont...