I would do everything possible in my opinion to keep from using deadly force. I think most people underestimate the amount of trouble/grief/cost that even a justified self defense shooting could bring on you. Like say if you were involved in a shooting, but the police cleared you of any charges. Then, I don't know, maybe the president of the United States brought a lot of attention to the case, and then you found yourself back in jail, awaiting a trial, where you were already guilty in the media's eyes, and your life was going to super difficult for at least the next few years.
Like many of these hypothetical/subjective scenarios, there is no right answer for everybody. Even "erring on the side of caution" means different things to different people