both fights aren't very interesting but if I had to chose I would say Maidana. He did more with his one win over Broner then Khan has done on his "comeback" ever since the Garcia fight.
This is why I would definitely rather see Floyd fight Khan than Maidana. Maidana would look a few leagues below in terms of speed and skill. At least with Khan he can compete in terms of speed and there's a good chance of there being a KO. I don't think beating Broner is really impressive.