With Discovery, I get paid to shop at incredible connection, cape union mart and a whole bunch of other stores. Keep a Discovery card and an FNB card for the best of both worlds.
In fact, if you play it right, you can get cheap or free gym, free internet, 15% back from fuel, 4% back from online shopping, and at least 10% back from a whole bunch of other stores. That is only with using the right card (Discovery or FNB) at the right stores though.