When you travel regularly, frequent flyer programs are the first and most important item to sort out.

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Airline frequent flyer programs, seating, aircraft and computer systems vary widely from airline to airline, which can make redeeming miles or points across programs, or even gaining access to far-flung airport lounges, inconsistent and frustrating.

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The perverse result of frequent-flyer programs that award Million-Miler status is that they create a Doughnut Hole incentive for some of their best customers to fly on another airline.

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