You do need to check the climate. Cape Town in Aug/Sep could be rather cool, if not cold and wet. By the way, this is peak time to travel north to Namaqualand where the desert transforms itself into a vast floral tapestry. It is one of the world's greatest natural wonders. The further north you get, towards Namibia, the better it gets. I think this time of year is good for whale watching near Cape Town. It's also good for game viewing in the Kruger - it's the dry season so you can possibly dispense with malarial precautions. I always think that for a true wilderness African safari you need to go to ZimZamBots as well as Tanzania and Kenya. South Africa's game parks are just a bit tame.

Aug-Sep is perfect weather for the Seychelles and Mauritius. Madagascar, too, so check out the Hotel Anjajavy. It's a shame South Africa's dramatic beaches are not really user-friendly if you want to do more than just walk and admire the views. Cold currents and you also stand a good chance of being eaten.