I don’t know about the missionary program per se but I have had contact with Regnum Christi. I believe most in RC see it as a great thing, but google “regnum Christi regain” if you want to see experiences of others who have not found RC as good.
The Mission Corps are young adults who are part of Regnum Chrisit and dedicate one year to direct service. More info is availible somewhere on the website (I can’t remember where) www.regnumchrisit.org.
As a Legionary I am, de facto, a member of Regnum Christi.
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