darth vader is weak noob. Robot is a pro
Well, Vader has the force. Force chokes and saber throws all the way!
Since I like to pretend that the prequel trilogy never existed... This is a very easy decision.
While I believe Grievous is a better duelist, Vader's force abilities take the win by a long shot he can easily force crush the General or use a powerful force push to through the General off guard.