For those of you who have traveled to Southern Africa in the last several years, did you use a US based or a SA based travel agency. .and what were your considerations?

I have planned a lot of Asian and European travel independently and never used a travel agent, but feel that Africa is bit more daunting, with more choices, and more on the ground concerns with safety, health, and cost and lots of transfers.

Im not necessarily looking for a specific agency to work with, just what made you decide to go local or use a US based service, espcecially when it is easy to work with anyone anywhere.