It's just a little surprising that "Vera Cruz" is not as well-remembered as some of the other westerns of its era, because it has a great deal going for it. Burt Lancaster and Gary Cooper both give fine performances that get the most out of their characters, and the story, setting, and photography are all nicely done. It's an entertaining and often suspenseful movie that is well-crafted with plenty of action as well.
The setting in late 1860s Mexico is the kind of setting that has often produced some of the finest westerns: a confused struggle where loyalties are up for grabs, no one can be fully trusted, and issues of right and wrong are easily clouded by personal desires. Joe and Ben (Lancaster and Cooper) are right at home in this atmosphere, and the story makes good use of the possibilities.
The opening sequence is a fine way to open the story, with Joe and Ben confronting each other as well as the military. The battle of wits and weapons is interesting in itself, and brings out a great deal about the characters right from the start. It is quickly clear that Joe and Ben have some important differences, but also that they will need each other before long.
The location filming in Mexico is an important part of making it work so well, with plenty of interesting sights to go along with the realistic backgrounds. The rest of the cast is also good, and they get a few moments of their own (Sarita Montiel, in particular, grabs your attention), although it is always Lancaster and Cooper who are the center of attention. It all makes for good entertainment, and it has more than enough substance to it as well.