Although I haven't done the race before, I did cycle the route whilst on holiday in Knysna. The route does have it's fair share of climbs, just after Knysna, between Buffalo Bay and Sedgefield, which you will get on your way back again, so save some.
This is what I know about this race. There is a lot of rolling hills (big enough for group splits), Hoekwill ?? 6km of very steep climbing, if you put together the "Taal Monument" in Paarl X2, you would be on par with this climb. And the most dangerous part of this course is when you hit the train track at the botton of the climb at about 70-80km/h. When you see the train track board, slow down to "standstill" and cross the lines. This track rail track will put you in hospital for a very long time. It's a tough race but not tougher as the new route Argus. Another difference from the Argus is the weather. July is a wet and rainy month in Knysna. More MTB weather.
I know the area fairly well but have never cycled it. The route is supposed to be comparable to the Argus in difficulty. There are not very many flat sections. Its either up or down. I reckon it could be quite tough. I'm sure I will be doing it.