I have a 1meg line, with a 20gig cap
performance: Latency slightly above other ISP's at same line speed. Speed can usually be decent. Often experience semi disconnects and sometimes very poor speeds. - Telkom is unable to explain, but usually gets better if the port it changed.
Support: Dreadful usually, often wait ages for a consultant. Consultants vary greatly in respect, and often are not really able to help you at all, and tend to mis-interpret what you desire. Their "call you back" service only works about 1/5 of the time. Improves greatly if you can convince the consultant to speak to a manager.
Value: My current account is fairly decent value for money. The 20gig cap is greatly priced compared to other deals in SA. Line rental is still rather pricey however, and there is no compensation for when your line is down.
Overall: It is internet, works as it should, mostly. Generally quite happy. But slow response and bad customer support when I experience problems once every 4-6months brings down my overall satisfaction.
Improvement wise:
The call center is in great need of dedicated workers, who actually care about the customer.
More technicians are obviously needed. (Although that is a more line reason, and not so much ISP)
The staff in the call centers need a lot more training, and need more powers to help the user.
Well priced, home, uncapped deals are also something they really need to consider.