If you're in the middle of being physically attacked, way too long. And, if you're being attacked, you may not have both hands free to even do it.
Use of force scenarios aren't all cozy like on TV, where the homeowner wakes to a noise in the kitchen. Sometimes people wake up to a hand closing around their neck.
I understand what you mean, but hopefully I would have some warning from my alarm system. With small kids, there is no way I am leaving a round in the chamber. I am not going to put a stupid trigger lock on either.
My kids are trained not to touch weapons without an adult or their older brother, but I was a kid once and boys are boys.
Right now, they would have some difficulty chambering. Hopefully, with training they will always be safe and respectful with these tools.