Originally Posted by
ravisurdhar
... I'll get 550 points (=$5.50) if I book through AmEx, but I also lose $7 upfront (net -$1.50),
It appears you are valuing Membership Rewards points at $0.01 each. They are potentially worth more, if you transfer to an airline frequent flyer program and redeem for otherwise expensive tickets, such as intercontinental business or first class. Once you decide on a fair valuation of the points, based on your redemption pattern, this becomes a simple arithmetic problem.