I went out to SA last year to do 100 hrs hour building. I booked with a flying school in the Johannesburg/Pretoria area, but after 3 weeks on the ground and no flying I decided to drive down to the coast in search of better weather. (You can get fog / haze and thunderstorms in the summer inland).
I ended up at a Flying school at Virginia Airport near Durban. I paid up front and it worked out at about £60 per hour for the C152 and £65 p/h for the PA28. They also let us have a C152 for a whole week for just ourselves if we guarantee about 2.5 to 3 hours flying a day. In 8 weeks, I flew about 6 days a week. It was blue sky, not a lot of wind, no storms etc. every day. There are very nice land aways.
From Durban:
1 hour away - Richards Bay Airport
1 hour away - Margate Airport
1.5 hours away - Port St. Johns Airport (on a mountain)
All these airports are on the coast so is easy to find. We even flew down to Port Alfred, which I logged 7 hours flying in 1 day.
Beautiful scenery, lots of planes, lots of places to go etc! So I would recomend going to Virginia Aiport. The people are also very friendly at VFS.
Any more questions, or want photos, let me know!
EKE