I agree with westllen - small Sebenza or Mnandi? The best answer is yes. (i.e. both)
I EDC a large regular Sebenza. The small regular Sebenza is for when I want something lighter, when wearing shorts, or smaller, when flying somewhere with a 3" blade length restriction, or working somewhere the large Sebenza raises eyebrows. The Mnandi is for dressing up, carried either in its pouch, or clipped inside a dress shirt pocket like a pen. That can lead to interesting conversations when someone sees the Ti clip and wants to borrow or look at the cool pen.
If you can only afford one now, I guess the question is whether you want the smaller size, in which case I'd say go for the small Sebenza, or a dress knife, in which case I'd go for the Mnandi. On the other hand, there's always the wood or leather inlaid small classic Sebenzas. Decisions, decisions... So many knives, so little time (and money) Since anticipation is half the fun, enjoy!