I'm not sure you know what a rap style is. The subject matter of a rapper is what your referring to, and thats only one category of the art. The question is "who is the better rapper?" so comparing flow, style, dialect, and subject matter which might take a little comparing and contrasting (grade school level technique) who comes out on top in your opinion?
No, what I intially said is true. Two totally different styles and two totally different messages.
Thats like saying "Whos the better athlete? Lebron, Peyton, Pujols, or Tiger Woods?"
All rappers dont fall under the same category, just like all athletes dont fall under the same category.