Southern Africa particularly fits the bill. It's climate is temperate, the land is fertile (when farmed by people who know how to farm), and it's not in the malaria zone.
If the Chinese settled a few million energetic young men who knew how to shoot a gun as well as farm, they would do well
The Chinese aren't interested in land, they're interested in things like coltran and oil, and access to markets.
Rhodesia has incredible farmland. The Chinese farmers can take over and make their own plantations once the whites are all dead and driven out. The blacks will work under Chinese who will be ruthless compared to the white farmers
http://www.amazon.com/Farmers-Forty-Centuries-Organic-Farming/dp/0486436098