True, of course all the standard caveats of making sure they are trained with them. I have zero concerns about a snub as a back up and while I wouldn't recommend two revolvers as an alternative to a semi-auto for carry I wouldn't be as concerned with a revolver as a primary if I was carrying a second as a backup. Of course having that second revolver also gives you the option of arming someone else.
I currently don't carry a back up, just a J frame when I'm on my own or semi-auto if I'm with family. As a civilian (no LEO background) I do worry about extra scrutiny that may result from carrying two guns but I suppose that is what carry insurance is for.