I do this about 6 times a year, the most recent being about a month ago from T5. I used to opt for the earlier flight and head to the arrivals lounge in the Intercontinental Hotel. It's a 5 minute walk, if that. It is an excellent lounge but at that time of the morning the breakfast service is epileptic. recently I've switched to the later flight and have a decent time in the lounge, simply to let the awful traffic subside. I usually have an Avis hire car which is right next to the hotel, but there's no point being on that road heading towards Joburg until around 9 or so. If you're off to Pretoria then it's a bit better and the early flight is OK.

Best Ferret.