Sometimes it looked like Unga wanted to punish people for coming after him (which was very fun to watch), but I do think there were times he could have gotten a few more yards had he dragged them like Jamaal. Of course maybe after punishing a guy all game, they are less likely to bring you down later in the game. Who knows.
All I really know is that I have loved watching both backs. I remember lots of times thinking with Unga, "Man I am glad he's on our team", and I have also thought the same thing about Jamaal - some of his runs just brings a smile to my face.