Although this version of the Jesse James story is more factual than most, it's at the expense of entertainment. Robert Wagner simply does not have the charisma that the character needs for us to believe that so many men, older than he was, were willing to follow him. Nor are any of the characters particularly well drawn, which doesn't give the actors much to do. The story is told in flashback form, starting with Northfield, but this does not seem to be to the film's advantage. The first 10 or more minutes are spent with the Northfield posse trying to track and find the gang, and because there are no characters to be invested in, it's rather dull. Later, when the flashbacks catch up to the present, we see some of the same material again. Interestingly, the screenplay credit says it's based on Nunnally Johnson's screenplay for the 1939 version with Tyrone Power. That version took a lot of liberties with the history, but is far more entertaining.
Technically, the DVD looks fine. It's a clean print, nice transfer with decent color. A trailer and a newsreel clip comprise the extras.