I carry three for business and personal....I personally use a Centurion (and Platinum before that) American Express (if you frequent ME airport clubs, make sure it's a ME issued AMEX), which provides you access to multiple international airport clubs, itemized billing, and the ability to defer travel expenses without penalty.

Also, the benefits package of a Centurion or Platinum AMEX is quite good, as it allows you to collect rewards, use them for virtually anything. Also comes with concierge, generous personalized offers, etc.

As mentioned above, many places don't necessarily accept AMEX, so a VISA Signature Card (choose something that you like...air miles, etc. In fact, the Qatar Airways Visa Card is earning a good rep..I'm thinking of applying for one myself) works the trick as a reliable number 2.

In addition, Diners Club, although it isn't widely accepted, is the BEST card for access to Middle East airport lounges if you don't have an ME issued AMEX...