OR Tambo airport is better than HLA because it is closer to the city centre and all the major attractions and sights to see in Johannesburg. The airports efficient public transport services either by train, bus, or shuttle will get you to central Johannesburg in 32 minutes or you can opt for a faster means by taxi or Uber. OR Tambo has 2 terminal buildings which can be tiring to move around but compared to Lanseria airport but it is still a better choice if you can patiently go through the long queues at immigration, and flight delays. The airport is served by top airlines with flights to many destinations across the seven continents except Antarctica. Although, it has efficient public transport system with more facilities, it also sees more passengers than Lanseria airport so long queues and flight delays should be expected.