I will be in the Timbavati and Klaserie areas in South Africa, My understanding is that it's a huge area.
Timbavati and Klaserie are huge areas indeed, but it's bushveld.
Shooting and observation distances are close.
The old saying of "buy once, cry once" is very valid when it comes to purchasing binoculars. A high quality 8x42 or 10x42 will stand you in good stead for many years to come. As we get older, we start to shake a little more, and our eyes don't work as well as they used to, so this needs to be considered when buying an optic that you'll use for next 20 years.
The only advantage that a 10x42 has over an 8x42, is slightly higher magnification.
ALL the other important advantages go to the 8x42.
Better Stability, Better Field of View, Better Depth of Field, Higher Light Transmission, Lighter Weight.
It doesn't help having the extra magnification, when you can't keep the bino still enough to judge if the kudu across the valley is 52" or 56", or to see how many points that bull elk has.
I've literally spent months behind a binocular, and you won't find a 10x anything in my house.