MJ was a true journeyman. He was solid but not spectacular. You could count on him to be on the field every game but would not wow you with big plays. In my memory banks he seemed limited in range because of his speed but once he had the runner in his grasp it was over. I don't remember his coverage skills so I won't speak to those. MJ on this team would be a backup.
The Boz on the other hand played lights out for a very short time. He did more damage to his body than it could take after his steroid use in college. His shoulders were coming apart but he was fun to watch. His decision to consume high levels of steroids in college doomed his NFL career.
He wouldnt've been nearly as good in college without the steroids. Probably not a high draft pick without juicing. His body was holding more mas than it was built to carry - this very likely is why it broke down on him. I heard his teamate Dave Wyman talking about him and Wyman said he liked Boz and thought he was a good player and good teammate for his first two seasons.