Hi Skaz--you and I up at the same time, except it's a little late for me and kind of early for you. But the sun is up here; I wonder if it's up in Botswana yet?
To answer your question: All of the above.
But, by and large, the most common airplane will be the 207. There are a lot of cubs up here, but if we're talking about what delivers the mail, it's the 207. Also the Cherokee Six, Piper Navajo, Cessna 402, Caravan, Twin Otter, CASA 212, Shorts Skyvan--probably all the same equipment you see in Africa, with the exception of Soviet aircraft...
Almost every plane has GPS or at least LORAN. There are plenty of VORs and NDBs, but the problem is staying high enough to receive them. Often you'll be scud running at 500 feet (never lower, of course) and be 80 miles away from the nearest VOR or NDB. Ironically, you can almost always pick up the local AM radio station with its 50,000 watt transmitter (so you can always find town).
What aircraft do you fly?