As burmans says, a number here are members - like me.
I love mileage plan. Good value buying miles when bonuses are offered, (unfortunately not as good as when the dollar was near parity), and good selections of airlines to redeem on reasonably cheaply - they go across airline alliances, so you are not stuck with the same mob if you were OneWorld for instance.
Pretty easy to book with them - Cathay and I think one other you have to call them, but when on the line they are easy to deal with; else its book on line.
And they (or at least in their original incarnation) are good to fly on!!
