Hi Tony
I've played Royal Cape a bit, it's not bad, worth a day out. Of the other Cape Town courses I've played, Clovelly, which has been mentioned, is very pleasant, Atlantic Beach is good, Steenberg is average, Rondebosch is fair and not worth detouring to play.
Outside of Cape Town in Somerset West is Erinvale which is good, Strand is fair.
On the other side is Pearl Valley, Jack Nicklaus, it's good and close by is Devonvale which is fair.
Then there is also Arabella which is good, about an hour from Cape Town and worth taking the trip.