Where to live in South Africa?

I might have the chance to move to South Africa with work, and wanted some advice on where to live and the real security situation. I will be travelling quite a lot around the neighbouring countries, so want somewhere that is safe to leave my wife and children while I'm away. We've visited Cape Town and loved it, but did not see Pretoria. I have a feeling that the company will want me in Pretoria, so I'll need a pretty good reason to opt for Cape Town.

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