sb wrote:
I really like my 100-400L Canon zoom lens. I debate getting a Tamron 150-600 for an African safari if I go next year. It is a very heavy lens for walk-around use. You would definitely want to take a large bean-bag to help support it on the vehicle while on safari. Everything I have heard and read about safari photography emphasizes the dust. I suspect it will be a good idea to take a second body with a lower-power zoom - perhaps even a point-and-shoot - to use for landscape shots, etc.
If you "walk around", only your companions will need cameras. Your camera may survive though.