Cavorting Cheetah
I think if flying SAA it will be 340 / 330 rather than 747.
Vanja
Also with SAA flying at Night you will not get the rising heat of the Sahara, which you can get on daylight crossings, which does cause turbulence. ITCZ has always got to be crossed, but as has been said by PAXboy weather radar has improved, but as always keep that belt on when sat down. I think the biggest shock you may get when flying over Africa for the first time is how big she is (just see how slowly the little plane moves on the inflight map!), and to a degree how few lights there are below you.
Have a good trip.