The Michaelangelo is another option if you want access to a modern shopping mall in Sandton and some nice restaurants around Mandela Square, then the hotel is literally on top of the shopping mall.

The Rafael Apartments is on the other side of the Square if your want something a bit more than just a hotel room.

Its still a 30 minute drive to/from the airport without traffic. Saxon is about 35-40 mins. I have always taken hotel cars or the travel agency has arranged for a car service and avoided taxis in Jo'burg.

Airport Intercontinental is 1 minute walk, so its best in terms of ease but not a lot of choice in terms of evening meal.