Checked the GBP/ZAR rate. Pretty devastating. I wanted to do bit of heli flying there, after my US comm, but the mid-market rate of 10 Rand to Pound (even at its low) is pretty much a no-go. It's cheaper to fly in Australia or NZ, comparatively.
As for fixed wing, it was reasonable, but I doubt it's any cheaper now than in some nicely priced FTO in the US. For short trip, yes, the lack of hassle with SEVIS/TSA/visa/school 'admin' fees etc could make up for going to SA for PPL, but for the whole training, hmm.
That's just pure economics. I'd still like to do some flying in SA, seeing the Capetown backdrop in real, etc. Unless there's another ZAR crash just like couple years ago, I can't see the reason only to have the best deal for limited budget.