at last a question I can answer!
You can get a work visa in South Africa to work as a helicopter pilot - I have just got one. It took quite a while (about 3 months) and cost me R8000 (about 700 pounds) and is valid for three years. There is quite a lot of paperwork to plough through though, and South African civil servants are no more efficient than any others, IMHO. If anyone wants a full list of what's needed for a work permit, pm me.
I did my training in Durban and loved the place so I decided to stay. A mate of mine did his in Cape Town and said the weather was not as consistently good as Durban, although still much better than the UK. Joburg with an elevation of 5000 ft will give plenty of opportunities to practice limited power manouevres, especially Dec-Feb, when the temperature can reach 40 degrees C. plus. In my experience South African training is of a very high standard too - unfortunately the Rand is pretty strong at the moment so it's not as cheap as it once was; R2000 per hour (R22) is about the going rate.