Stewart is never bad, IMHO.
I can't stand Kanye West on general principle, so you already know my feelings here. And no, I don't hate hip-hop. I just don't like Kanye. Having him rap over the Police is like saying, "Here's your wondrously prepared creme broulée, and we decided to sprinkle some liverwurst on top."
I mean, it may be okay on its own, but it just served to fuck up my tasty treat.