I just finished a 10 day trip to South Africa and I got good values out of my Prokard Gold membership which costs 1500R. I was able to use two buy one get one free at the Protea Mowbray hotel and redeem a free night at Protea Mossel Bay. I was even upgraded to a suite at Protea Mossel Bay.
Breakfast and dinner are 50% off with a party of two at the Protea Oudtshroom and Protea Mossel Bay. Some hotels simply deduct 50% off the bill with food and drink. The official benefit is 50% on food only.
You can redeem free night or BOGO night when there are still rooms at the Best Available Rate.
On a rough estimate I saved about 5000R on my six nights stay at various Protea hotels.