I have never seen the need for a backup and am unlikely to ever get myself in a position where I might...
Some time back, I had called a friend....it was a Saturday near lunch time....I swung by his place and picked him up on the way to a restaurant. As we ate lunch, we talked about lots of things....mostly gun related as we spend a lot of time together at the range and just like to shoot.
I asked him if we was carrying...."No, I didn't grab it since I knew we were just going out for a quick lunch."
He asked me if I was....."Yep, one on my hip, the other in my pocket."
"You carrying a backup?" he asked.
"Yes. If you aren't smart enough to carry your own, I figured I would need one available for you."
If I am with a friend or family member, and I know they can handle a handgun, I have no problem providing them with my BUG should a situation arise where two are better than one. And as was already stated...."two is one and one is none".....I've followed that saying for many, many years. It's why I carried spare axle shafts, u-joints, water pump, fuses, fan belt, radiator hose, etc. on the trail when I was actively 4 wheelin'. I never ever had to use one on my own vehicle....but many friends thanked me for what I had along when they otherwise would have been stuck in a very bad way.
One other point....I chuckle when I hear people make statements like..."I live in a nice part of town and never allow myself in a situation (ie., go to a bad part of town) where I would ever need more than my pistol and the magazine that is in it."
Gee....I wish I was able to control my world so well that I could stop someone from the bad part of town from coming into my neighborhood to commit a home invasion, burglary, carjacking, etc. Not too hard to realize that a burned out meth head would not want to try any of those in his own POS neighborhood?