Pit Bulls are great dogs right up until they kill a kid. A buddy had 2, and they were great dogs. I played with them myself. Smart, they would mind, and they loved to chase a stick. Great dogs until the little girl next door got off the bus and ran to show her mother the picture she drew that day. They buried that picture with her.
I have this one as my avi... well, i found him as a stray years ago and came so close to just taking him to the animal shelter. I sure wasnt planning on having one but he turned out to be the most gentle dog I've ever had unless you are a cat. Now I did the acid test when I first got him. the top his head was bloody and he was skinny as hell and dirty, so I picked him up and put him in the tub. He let me do that without a hitch, without even knowing me ..so i figured right there he wasnt to bad. To this day he wont bark at the mailman, anyone can come in the house or back yard and he greets them with a rub of the nose.
But I will agree that because of their power and what can happen if they tangle with another dog or for some reason or things go sideways... you have to always have your eye on them in public and I keep mine on leash.
Never leave them alone with a kid and make sure you have a secure yard... very simple rules to follow.
The other thing with these dogs I believe is they need to be extremely socialized at a young age I believe... meaning being around lots of people, and other animals .. and going out very often away from the house. I believe it does something positive for their mind. In that respect they are not unlike people, I mean if you kept a person tied to a tree or in a cage their whole life they may develop some unpredictabilities.