Verdict:

At the beginning of the film the opening credits keep interrupting the movie and it’s really annoying. Now moving on.
The film is about the adventures of a gang of outlaws, and to a lesser degree, a gang of mercenaries hired to bring them down. The new world is closing around the outlaws and the old age is also starting to catch up with some of them. As far as Westerns go, this is a previously trodden premise, but the film succeeds in strapping enough meat onto that skeleton to make the movie interesting and exciting. The storyline is loose – more of a set of adventures rather than a cohesive whole.
A lot about The Wild Bunch feels like a modern film. It is quite gritty; the music has modern rhythms; and the characters are dark. In older westerns, whenever bandits are made to be the protagonists, they are also made to be misunderstood souls, full of heart. In The Wild Bunch, the outlaws commit some pretty reprehensible acts.
Perhaps the largest problem with the film is that it is not consistent with its characters (and by extension its story). The film starts showing the bandits as crazed violent people, but the creators could not resist adding more honour and humour to these gangsters, perhaps out of fear of making them too unlikable to the audience. And so, towards the end of the film, they start acting more and more heroic. Two of these guys in particular are portrayed as greedy criminal sidekicks in the beginning. Their reasoning for change is: “Why not?”, as one of the characters put it.
“Because it’s completely uncharacteristic of you and there is no reason for you to do this,” someone should’ve answered, but no one did.
In fact, the whole tone starts shifting together with the characters and becomes more and more light-hearted towards the middle of the film.
Besides this strange character identity crisis, the acting is powerful. Of particular note is the Mexican warlord played by a gentleman named Emilio Fernández. On paper that character is just a power-hungry warlord but the Mexican actor breathes life into the character with facial expressions. He is perhaps the most memorable character in the film. There is, unfortunately, a good deal of overacting, like people laughing hysterically when there is nothing funny to laugh about. I should probably stop complaining about this, because this is the case with almost every movie that was released before the 70s.
It has good atmosphere with its smoky Mexican villages and bath houses and mountains. The sweeping landscapes are, of course, present as the staple of Westerns. Ironically, with its modern style, it also somehow borrowed a modern cinematographic faux pax: the cuts during the action scenes are too fast. You lose track of what is going on.
The music does not have a memorable tune for you to whistle, but is nonetheless interesting because it has a lot of modern asymmetry, with many different instruments coming in to do the various tasks required using special rhythmic patterns. There is a recurrent little tune, and when I heard it, I immediately felt that the creators were ripping off The Magnificent Seven, until I found out that The Magnificent Seven came out 10 years after this movie. Food for thought?
This film is not perfect. There are little things like a scene where you hear a man talk, but can see that his mouth is not moving. There is an issue with character development and mood inconsistencies. There is just something off about its whole structure. Having said that, it still feels worth watching for its off-beat modern violent delivery and decent atmosphere.