The Balalaika is within spitting distance of the JSE but the Hilton is also within very easy walking distance. (The IC Towers is closer than the Hilton.)

The trouble is nobody walks in Sandton and the pavements are often terrible with lots of obstructions from building operations. It's like trying to walk in LA or Doha: you feel a bit like an alien because nobody else seems to be doing it. Having stayed at the Hilton - or the Crowne Plaza next door - and walked to my meetings in Sandton, I can vouch that it is definitely very doable.