I don't know what year it was. I am sure someone does because several members are far more familiiar with ROAs than I am.
But at some point Ruger started roll engraving a warning on the top of the barrel. It think it says, "Hey Fool! Stop looking down the barrel when it is loaded capped and cocked!" or some such. That I am aware of, there is no difference in the components, features or manufacturing that makes the non-warning model more or less desirable. Just something for people on black powder forums to talk about.
Cleaning revolvers is (to me) part of the fun of owning and shooting them. It is just that IMO Remingtons are more fun to clean that Colts or Rugers.
My reading of history convinces me that most bad government results from too much government. Thomas Jefferson