Most scopes going to Africa (on big bore guns I sell or fix for clients) sport the following.
Fixed 2.5
!.5 to 5 x 20
1.75 to 6 x 32
2.5 to 8
Yes, I know there are tons of 3 x 9's and even bigger variables going but I also know that you want a scope that is close to the bore line of the barrel. You don't need real high end power in Africa near as much as you need field of view and...if the scope is available in the 4A or hvy. duplex reticle I put that on too. I love the 2.5 to 8 with the 4A reticle from Premier. This is a small scope that mounts low, big field of view and still plenty top end. Easy to get on a moving target fast and still easy to shoot something like a P dog if necessary as you have plenty of fine crosshair in the middle.
I do not like detachable rings as I see no reason to take a scope off unless you have damange to it. Then I take the proper wrench or screwdriver that I have with me in camp or my truck kit and take it off.
As to brands that I see going....Leupold is #1 with the assorted European scopes next.