Brandon Marshall is a far higher risk to end up in jail, suspended, or embarrassing the franchise. He has been arrested numerous times. He has been suspended by the league, and by the team for conduct detrimental to the team -- for not practicing hard. He's been benched as well - and for the final game of the 2009 season for not showing up for physical therapy. He was involved in the tragic shooting death of teammate Darrent Williams following an altercation in a night club. He's been ordered to undergo anger management counseling as a result of domestic assault charges. He does not appear to be an easy player to manage.
While clearly kooky, Owens passes the football-is-important-to-me test. He plays hurt. He trains hard. He tends to burn his way out of town, but at this point in his career he probably isn't looking at a five-year deal, and he might have matured.
Both players appear unstable. Owens is a question mark, and probably needs a strong support system after football. Marshall is a huge red flag, and given his team suspensions, clearly has other priorities than football. Belichick seems to have an issue with players who do not show up on time or practice hard.
I would not want Brandon Marshall on my team.
I would not want to give up a high draft pick for Marshall.
I would not want to carry the salary cap charge for Marshall.