How Do You Choose Your Favorite Rap Artists?

Have seen a lot of fights and comparisons here. For instance, like pitching M.I and sauce kid to decide who raps better. Some say M.I while the others pick sauce, but what matters most is the criteria he/she used for making a choice. Now the question is, what qualities makes up your favourite rap artists?

In my own opinion, as long as you have the sophisticated lyrics and the coherent flow, I make my choice based on a nice voice. I like rap artists like; the game, DMX, Nas, lloyd banks, M.I. just because of their voice. Though eminem is good rap artist, I dont buy his CDs because I dislike his comic voice together with 50 cent, jay-z, snoop dogg, lil wayne etc