He will be fine. At 14 he can play pretty much anything (im currently 18, had to go through all that guff with my parents until I was 14 also). At the end of the day as long as he understands its a fantasy, which im sure he does, he will be fine.
If you're still asking these questions in 2012 then you must live in a different world. Kids don't care, parents care less and the world is going to *** anyway. So I don't think it particularly makes a difference, as those are all games with similar content (i.e. violence).
He will be fine. At 14 he can play pretty much anything (im currently 18, had to go through all that guff with my parents until I was 14 also). At the end of the day as long as he understands its a fantasy, which im sure he does, he will be fine.