Manziel isn't going to translate well to the NFL in my humble opinion. He's an unbelievable college playmaker, but short, maybe 4.55-ish speed, average arm strength, limited pocket presence.... LSU game anyone? How many of their D were drafted? 6 or 7? Keep him in the pocket with the speed of NFL defenses and he's fair to middling.
As has been mentioned 100x EJ has such horrendous footwork it makes me cringe. He's had a couple strong moments. I can't close the book quite yet myself but im getting there.