This western, I believe, is the second one I ever recall watching (after "The Range Rider") and the first recall with great fondness and a knowledge that a lot of people also liked this show. They had to, to have it run six years.
To be honest, I remember the Cisco Kid's partner, "Pancho" (Leo Carillo) more than I remember him, although Duncan Renaldo is not forgettable. He was a charismatic good guy, a real straight arrow and a great role model for small kids. I was the perfect age (6-12) to enjoy these episodes of a western that was made more for us in mind than adults.
Pancho, if I recall, mainly provided comedy relief...and that was fine with us kids. We loved him. You couldn't ask for a more loyal sidekick, even if he wasn't the most brilliant person.