I think we may need to put things into a little perspective here
A violent crime in the UK generally may be getting the crap kicked out of you on a Saturday night when you've been down the pub and drunk too much (although of course there are more serious crimes).
A violent crime in South Africa is more likely to be having your head blown off on your drive outside your house all for the sake of a mobile phone, or having your house broken into and seeing your wife and daughter gang raped in front of you just before you are stabbed to death.
Having had a fair amount of exposure to stories of SA life in the past, although the figures may or may not be right, I dont think you can really compare crime in SA to crime in the UK