To answer your question, I’d say it depends on the time you have and the vehicle you’re using.
If you need to get between these two cities quickly, flying is obviously the way to go.
If you’ve got a bit more time, the paved road via Nata works well. A regular car will do, but a 4x4 would let you visit the national parks of Makgadikgadi Pans or Nxai Pan.
Personally, I drove a 4x4 with a rooftop tent on the track between Maun and Kasane a few years ago.
Apart from the fact that it crosses a very wild part of Botswana, the big draw is that it runs alongside and through two of the country’s most famous reserves: Moremi and Savuti. Don’t take this route if you’re in a hurry because Moremi in particular is really worth lingering in—it was my favorite reserve on the trip. If you don’t plan far enough ahead, it’s not easy to find a place to sleep inside, but it’s easier just outside, near the Khwai River (where I saw loads of animals), between Moremi’s North Gate and Mababe.
The route continues through the Savuti reserve, where I couldn’t hang around because I couldn’t find an available campsite.
From what I remember, you’ll hit paved road again at Kachikau.
This route means driving on tracks where the sand can be very deep. It’s not always easy, but I managed without any issues even though I had no experience with that kind of driving.
You’ll also need to bring food and water supplies since there’s almost nothing available to stock up on along the way.
Mon voyage au Botswana :
https://voyageforum.com/discussion/pays-tswanas-botswana-d9819920/