Depends partially on what/where you will be hunting...just to play devils advocate, there are quite a few ways you could look at this...

Of the 1.5-5 or 1.75-6 in various makes I have, S&B as JPK mentioned, offers by far the best low light conditions scope...Swarovski is quite a bit better than Leupold again in low light which you might find on a leopard hunt...other than that, either would do fine..you also have to consider whether you want a dot, duplex (standard or heavy), etc..and again if you get too heavy of a duplex it can cover too much of the target at longer ranges..which are not common in Africa but they do occur..I have a heavy duplex on one of my .416's..and at 200 plus yards on an impala,..makes it more difficult to really "pick the spot"..

Again, if you were hunting more in S Africa and Namibia and I was using it primarily for plains game I would go no smaller than 1.75 to 6 and may choose the 2-7 or something in that range---if it fit the gun...think the Swarovski 1-6 is perfect but again, a bit on the heavy side---

If I was hunting in an area with dangerous game whether in Africa or in Alaska..would stick with one of the lower power scopes..have used 1.5 -5 or a 1.75-6 in Africa on numerous hunts..have never needed more...but on shots where more precision was needed I did use higher magnification, ie, croc brain shot..but really feel 5 or 6 power would have worked as well..

Ripp