Harmon could start in this league and has great hands. IDK if i ever have seen him drop an interception chance. That being said his mental lapses make me pull my hair out. Harmon had a chance to be the hero of superbowl 49. On that crazy catch late in the 4th he was right by the guy when the ball was knocked up in the air. Instead of doing anything (batting it away or trying to catch it) he just jumped over the player and basically did everything he could not to interfere with his catch.
I have seen a few plays like that where he just seems to think he is still in college or gives up on the play early. He could have iced the game there without us needing that Butler pick. So while i like what i see from him on the whole and would not cut him it is always in the back of my mind he might make a mental lapse in a close game like that.