Should you use just 1?
For any charges at a Marriott I use my Marriot Visa - 3 points per $ charged - It was invaluable during the double points promotion.
For Travel on AA I use my AA Visa - Double miles on all AA purchases.
Everywhere else I use Amex for flexibility so I can top off a variety of other programs thru membership rewards. (DL, US, Starwood)
I've now registered all 3 at IDINE so there's 10 points per $ on any of them. If I should find a IDINE restaurant at a Marriott I'd be happy!
[This message has been edited by sdix (edited 04-02-2002).]