Telkom had really good value for money. MTN are so rigid with their contracts, they cannot or will not accommodate their clients. They are like DSTv they charge you for service you don't need or want.
The best of what ??. Telkom has by far the best network with the worst service. Vodacom has the best Cell Phone portion out of the lot. If you listen to the "billions" Vodacom say they are speending every year to make their network better, they must of spent enough to have replaced it 20 times by now but it is still rubbish.
Vodocom. I have a MTN and Vodocom contract and I get more benifits and service and less hassles from Vodocom. MTN has a few issues and this is causing me to think twice about renewal.
I think it depends in the area you are in - for me, Vodacom works fine. But if I had to try another one, it would have to be telkom purely based on price. That said, I use so little airtime it is not worth the hassle.
I have been an MTN subscribe for about 10 years now, and quite happy with their coverage. Have never had a dropped call. Not too happy with their pricing though.