You can often tell whether a neighborhood is dangerous by looking for certain cues. Unfortunately, one of the signs I look for is totally useless here.
In the States, if you see bars on the windows and razor wire topped fences, you're probably in a bad neighborhood. By that measure, all of South Africa is a bad neighborhood. Even in expensive suburbs (in fact, *particularly* in expensive suburbs), houses have bars on the windows and razor wire. Some even have electrified wire along the top of their enclosing walls.
And most houses have signs from ADT, Chubb, or some other security company saying "Armed Response", meaning that if you trespass, some rent-a-cop will come and shoot you.
I'm guessing much of this is required by the insurance companies as a condition of homeowners insurance, but it is daunting anyhow.
I'm staying in the suburbs of Nelspruit, the capital of Mpumalanga province, in a neighborhood with a Southern Californian feel. Except for the massive amounts of security fencing. Oh, and the mean-looking dogs behind the fences.