take Shaq over Ducan in a heart beat. Shaq is a much more exciting player than Duncan, he can generate a lot more revenue than Duncan.
As basketball player, Duncan is more polished on both end of the floor, TD has more skills, bigger heart, the more importantly, he is selfless. He will never shout out "show me the money".
Anyway, I like them both, and I like the fact the people brought out these two names for the argument of "who is the best after MJ", NOT the Kobe/Tmac/LBJ/Wade.