On the issue of removing the scope: the first time I did not, and it was no problem. I decided to take it off the second time I went. Security in Johannesburg took exception, and the agent took it over to her superior. They mistook it for something else because she returned it saying that they mistakenly thought it was off of a rifle, and that's not allowed. Yikes. So it stayed on the gun for the return trip.
There is a thread somewhere about South Africa not allowing it anymore. I don't know the rules, but if you get someone who doesn't know the difference between a scope and a telescope, and you should be fine.
By the way, I use a tuffpak and like it very much.