Frankly, if it says "Roy Rogers," the odds are it will be good. And this one is. For several reasons.
One, the historical setting is very interesting. It's around the turn of the 1900s and this contingent of Rough Riders is returning to these United States ... well, actually, considering the time, to a territory of these United States: Arizona, and the border with Mexico.
The Rough Riders' leader, Colonel Teddy Roosevelt, is being talked about as a vice-presidential candidate
Roy Rogers nearly always played either himself or a character named Roy Rogers, which was the case this time. It seems an odd practice, but was also done with Gene Autry, among others. Often, it detracted and/or distracted from the movie, but here it doesn't matter.
Soldier turned Border Patrol officer Rogers is joined by, among others, Rusty Coburn, played by veteran Raymond Hatton, an actor who had been around since the silent days and who often hammed it up like a B-class John Barrymore but who, here, was restrained and believable.
Other talent, and I do mean talent, included the beautiful Lynne Roberts and former chorus girl Dorothy Sebastian, as well as the prolific Eddie Acuff and the almost ubiquitous Hank Bell, again uncredited!
Seriously, it's hard to think of westerns without thinking of Hank Bell, he of the handle-bar mustache and Western drawl, and a superb character actor. Here he got some lines and again showed he should have been given many more speaking parts and many more-important parts. Maybe he never complained but many of us, his fans, do.
Amazingly, also uncredited were Duncan Renaldo and George Montgomery. The latter had a small part, but Duncan Renaldo's character was very important to the story.
Chris-Pin Martin and the really talented I. Stanford Jolley were also uncredited even though Martin also had an important part.
So, even if the story or directing or music were minor -- and they weren't; they were quite good; after all, the director was Joseph Kane - - the cast alone makes this more than worthwhile.