GT summed it up very nicely.
I'm in that exact position at the moment. Going doe to Bristol on Sunday for the mandatory 2 week brush up course before my (hopefully) last set of exams.
The 15 IR hours you need to do is the minimum though. According to most of the schools I have spoken to people normally do about 20. Airspace is a lot busier over here than back in SA so things can get a bit out of hand.
As far as air schools in SA are concerned.... there are many many great ones. I would suggest that if you have the time and the money.... go down there for a couple of weeks and visit as many of them as you can and make up your own mind. I did my PPL at 43 most of my flying with Stellenbosch Flying club and my IR and ME with Cape Aero club. All great institutions.
Best of luck and I hope you get some results!
D