IMO while I'm sure the ATB center diff is nice, it's not essential. I did 15K kms over 9 weeks in Southern Africa in 2015 - rental Puma 110. They handle well stock and AFAIK the center diff isn't a weakness unless spun unlocked.
We had no fuel issues (Namibia, Botswana, SA).
Are you doing something security wise for the tub? I'd be concerned about only having the canvas.
We found the SA 4x4 forum a good resource, and the tracks4africa maps are great.
Steve
1985 County - Isuzu 4bd1 with HX30W turbo, LT95, 255/85-16 KM2's
1988 120 with rust and potential
1999 300tdi 130 single cab - "stock as bro"
2003 D2a Td5 - the boss's daily drive
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