dhwhite:
If I have not previously welcomed you to the Forum, I do so now.
As noted, the R9 is a DAO pistol. It has a long, smooth trigger pull of about 8 pounds. (In other words, you have to want to shoot it to shoot it -- and then you should shoot it like you mean it.) All of that, combined with a properly designed holster covering the trigger during carry, and (as previously observed) the "stuff" between the ears, constitute the safety.