The show was excellent. A little darker (emotionally speaking) than most Westerns, Robert Horton plays it excellently as a man who has lost his memory and is searching for his history throughout the country. It's the typical Kerouac-ish theme of roaming the country, that was found in so many episodes in the 60s. The plots are good. Horton is good. And the theme song, besides the Bat Masterson theme song, is the best one ever, and I believe Horton sang it himself.
While the theme and darkness somewhat resembles the Fugitve, robert horton was no David Janssen. And in the Fugitive, one got more of a sense of desperation; after all, Kimble was running for his life. What's the worst that happened if Shenandoah didn't find what he was looking for? He still had a good life. That's what subtracted somewhat from the show - the idea that "so what, he lost his memory".
But still, had the show lasted more than a year, other ideas could have been developed. It's a very good original theme, with lots of open space to work with. Not sure why the show didn't go beyond a year, but it's a shame. It was quality, and could have improved even further.