They chant eerily. They attack and kill. They use spears when rifles would be more effective. Their stupid moves (stopping in the village, getting drunk, leaving the children unguarded) outweigh their smart moves (raiding the fort and attacking the wagon train unexpectedly). In short, they're savages, and no match for our stalwart heroes.
She Wore a Yellow Ribbon--6.5
So none of these movies is a masterpiece, despite what the fawning critics have said. And Rio Grande, usually considered the weakest of the three, is better than She Wore a Yellow Ribbon.
For more on the subject of John Wayne and his movies, see Straight Shootin' with the Duke.
Below: Some of the human drama that makes Rio Grande worth watching.