I re-watched this movie recently and it re-affirmed my belief that Anthony Quinn is one of the great character actors. Man From Del Rio was obviously a low-budget film - not because it looks 'cheap' but because it was shot in a simple old-West town setting, much like High Noon, and because it is in b/w and doesn't have any of the really top-name stars. None of those things detract from it because it has a very good story, an excellent, taut script and fine performances all-round. (Well, with one reservation I'll mention later.) Right at the beginning of the movie, David Robles (Quinn) approaches gunfighter Dan Ritchey (Barry Atwater). He has spent the last few years learning to shoot so he could avenge those who Ritchey and his friends killed when they shot up Robles' hometown of Del Rio. When Robles kills the noted gunfighter the town offers him the job of sheriff.
But the town is crooked, basically run behind the scenes by the former gunfighter who owns the saloon, and Robles makes it apparent from the start that he is not going to play along. The townspeople even regard Robles as little more than just a 'tool' to keep order, not wanting to afford him equal treatment as one of their own.
Katy Jurado plays Estella, the assistant to the town doctor, and Robles has eyes for her. She has been in SO many Westerns, playing mostly the same role - the detached, cool, beautiful Mexican lady - but here she speaks her lines in such wooden fashion it's like she's reading them phonetically and doesn't really know what she's saying. Her inflection doesn't go with her words sometimes. It's not too off-putting but I did notice it enough to mention.
I don't want to spoil the story, and there is a lot more to it than this, but it's an excellent little Western with a good plot, well-written script and believable dialogue. I would recommend this to anyone who wants to see a less-well-known but still worthwhile Western.