In macaroni salad, I prefer Miracle Whip. On a sandwich, Mayo hands down. It actually isn't an easy question.
I alternate. Buy a jar of Miracle Whip and when that's empty, buy mayo. Mayonnaise has GOT to be Hellman's, however.
Miracle Whip Lite, thats some good stuff. Miracle Whip Free is awful though. The only thing I really crave mayo on is chick-fil-a sandwiches.