Prince is like Magic Johnson to MJ's Michael Jordan. Still great, but not at that same level.
Dude I will be the first to sing MJs praises, I have a Thriller jacket, the album on vinyl, and all of his other solo stuff on cd, I even have one of those Bad 25 Pepsi cans. But heres the thing with Michael, the majority of his best songs were neither written or produced by him. Prince basically wrote and produced everything, and the production level is definitely Quincy Jones level if not better. That being said, i've only got through like 20% of his stuff so far, so who knows.
I'm not going to say he's a better artist than Michael, but I think he may be a better songwriter/producer.
EDIT: im aware saying that michael didnt write his best stuff will probably bite me in the butt. Im specifically referring to the Temperton tracks, but yes he definitely became more active in creation Bad and after.
Muda Muda Muda Muda Muda Muda!!!!