Since Des.Tom's original post in this thread is now over a year old and he has now been to his trip to Tanzania, there is quite a bit of more information available with regard to mirrorless cameras.
Between the most popular brands of mirrorless, Sony, Fuji, Panasonic and Olympus, Sony makes a full frame mirrorless but is the most expensive.
I recently replaced my Canon equipment with M43 camera gear - a Panasonic Lumix GH4 and assorted lenses. It's quite an adjustment. I don't miss the weight but am still learning the features. Micro four thirds cameras seem to have a large choice of lenses as they can cross over brands. I have an Olympus lens for my Panasonic camera along with three Panasonic lenses.
Be aware that M43 is a 2x crop factor. So a 25mm f/2.8 lens is equivalent to a 50mm f/5.6 in 35mm (full frame) camera.
So it follows to multiply the Fuji aps-c 1.5 crop factor by 1.5 to get the equivalent of both the reach (mm) and f stop of a DSLR 35mm camera.
If the following website doesn't provide enough information for those considering the switch from DSLR to mirrorless, a search for "mirrorless camera reviews" will provide additional information.http://www.bestmirrorlesscamerareviews.com