I have to weigh in on this, too.
The biggest difference I remember, is I think Emmitt's skills were more subtle ... not as obvious or evident to the casual fan. He was the best I ever saw at positioning his body for contact ... would-be tacklers would slide off of him.
Tony once said, "I'm the type of back that your mother or grandmother would enjoy watching." So true. It's because he was a pretty runner whose skills were obvious. Tony's best attribute was that he had an incredible burst ... so sudden that it was breath-taking.
Now, they had some things in common. They both had superior instincts for making guys miss. Both were good receivers and underrated blockers. And Tony doesn't get the credit he deserves for running inside and for his durability. He was a very good north-south runner and could do damage between the tackles. And thanks in part to Landry's handling of him, Tony had very, very few injuries in his career, especially for a guy who played most of his career between 185 and 190 pounds.
Having said all that, when it comes to pure, natural God-given talent, they finish No. 2 and No. 3 among running backs in Cowboys history in my opinion. Duane Thomas was 6-2, 225 and moved like water flowing in a stream. Heck, Jim Brown was in awe of Duane's talent. His mind was just wired wrong to have a long, successful NFL career.
Dallas has had a great history of running backs, and I have my doubts about the youngsters they have in there now.