ZC gives us an element that we really didn't have. His top qualities are vision, balance and ability to get yards after contact. Among our RBs, it's really him and Dallas who are willing, even eager to run through an MFers face.
He is an excellent 3rd down back, equally good at pass pro and catching the ball.
He has adequate speed. Not the breakaway speed of Walker or Penny when he was here.
His game is being able to find the crease in a defense and then get there with both power and the ability to exploit angles and glance through tackles. He is the guy that will get 2-3 yards extra in the slop. Similar to Lynch -- but without the extra burst that will get him clean in the clear in most circumstances to turn a broken tackle into a 20-60 yard gain. He'll break the tackle, but probably get dogpiled a few yards downfield. And like Lynch, if he gets to the second level, he kind of seeks out a DB to punish downfield.
In all, he's a valuable component and will definitely have a strong role on this team. He does bring something that we don't have and have shown we like to have in our toolbox. Our running game just got a lot nastier.