Check this link: http://mybroadband.co.za/news/Telecoms/10663.html
According to this DC is paying R3807 per megabit per second for Seacom connectivity and they are sharing that on a 2:1 contention ratio
To make money they would need to sell each 256kbps package to 4 people minimum just to pay for the line and that would leave them with R250 profit for every 4 customers. This means that if 4 of us share the bandwidth we are each only going to get 64kbps if we are using it to download torrents or from RS ...
Of course this vastly oversimplifies the reality of how the contention ratios work out so we need to hope for a whole bunch of browsers (makes them sound like cows) to be able to get the most capacity out of our links.
Nobody has ever mentioned what price BCSgroup give if you rake a full STM-1 connection (155 Mbps).
Also rarely mentioned is the telkom ipc costs.
On a side not, a 20-1 to 50-1 contention ratio is the norm.