How bad is it? One of the worst B-westerns ever made.
Should you see it? Tough call. If you like B-westerns, I'd say yes (but you'll be disappointed).
This is one of the easier films of Robert Horner's to find. Horner frequently skirted the law when making films and was given leeway because he had no legs and only one eye. Almost every film he made was with a different fly-by-night production company, each intentionally bankrupted. He'd charge non-actors fees to be in his films for the exposure it would give them. Many of the worst practices of the film industry were pioneered by Horner.
In this, the hero plans to rob a stagecoach, only to be beaten to the punch by The Phantom, who robs while pulling a cape over his face. When his face is revealed, it turns out that he's a double for the hero. Then... stuff happens, confusing uninteresting stuff, with the requisite chases, brawls and shootouts. You'll see one of the worst fake mustaches ever, actors reading from cue cards, continual re-use of the same footage and the worst comedy-relief sidekick of all time, "Ptomaine Pete," played by Jimmy Aubrey, who was in 470 films, usually uncredited. Though only 55 minutes, the film drags.