Did not see this when it was released because, despite the draw of Harrison Ford and Danial Craig on the marquee, the premise seemed silly. Silly perhaps, but well done.
The story opens as an archetypal western with the hero seeking his identity, a strange artifact, a wise old man, and confrontations with both official and unofficial authority. Then the aliens show up. If War of the Worlds was plausible in 1897 (or 1938), then why not in the 1870s?
Good action, good special effects, good scenery. (Technical level of a made-for-television movie.) Predictable, but fun. Good hearted.
Excellent support for pop corn futures.