I have carried around my kids (well, they are ALL adults now) for many, many years and all of my kids (all five of them) are well versed in firearms except my oldest. My oldest (the only woman of the bunch) has never taken the time nor the interest in learning how to use her .357 magnum I gave her when she turned 21 or how to use her shotgun I gave her. Heck, I don't think she has ever fired a round! Now one would think that my daughter would not care for guns. Oh...just the opposite! She is a staunch supporter of ALL of our rights and understands that the 2nd Amendment IS the one RIGHT that keeps the others running smoothly. Time has passed and she is a mother of two now and living far away and is "too busy" to get her guns out and learn how to use them. Every time I visit her I try to find a bit of time in her schedule to go out and shoot. She home schools her kids and that in itself takes up most of the day. With all that said all of my children (except my daughter) can shoot many different types of firearms from shotguns to semis to pistols to revolvers and all of them own several different types of firearms. I did my best to educate them about our rights and how important it is to KNOW them all and exercise them all or we lose them one at a time.
As for the extra magazine....I don't know...I think if I had to use my G36 I could hit six targets up close with enough damage that they would stop their attacks on me or my family. Years ago I carried a big ole 9mm with 18 rounds in one magazine. It wasn't long after that I saw where TWO policemen were shot at by TWO assailants during a traffic stop and every single round fired MISSED. Both the cops and the assailants MISSED and they were only about 14 feet or less from each other. So....watch the movie "The Unforgiven" or skip to the end where C.E. does his thing in the bar. I know it cannot be easy to maintain calm during an event like that but if one can do it then every round fired will find it's intended target.
Oh, and everyone should reload if possible and teach your kids how to do the same! Heck, my wife's 10 y.o. has learned how to prepare brass and reload from me and actually helps me reload .223!