I think this has been done before, but anyways I'm going with Iron Fist. Since he first mastered ancient, mystic K'un-L'un martial arts, which no one else has access to, Daredevil is going to be fighting someone with a style he's never "seen." Whereas Daredevil, even with his ninja stuff, isn't doing anything Iron Fist hasn't encountered.
Iron Fist's mastery of his Chi endows him with more than a "brass knuckle."
In Contest of Champions, Daredevil had a slight advantage over Iron Fist and was sure he could beat him easily. Was DD being cocky? Who knows, but DD isnt one to be cocky. They also had a brief scuffle after that and once again DD was saying that he has to make it quick. He seems sure he can beat Iron Fist if he really wanted to. It was mentioned that Daredevil isn't doing anything Iron Fist hasn't encountered. However Iron Fist complimented DD in his fighting and even said "Very nice. What do you call that move?" "Hardly traditional, but it works." All in all, i say Daredevil wins 7/10.
Edit: Also Daredevil is VERY familiar with Iron Fist's fighting style considering hes teamed up with him on many occasions. Theres no way DD would be dumbfounded by IF's abilities at all.