I don't have any experience with the South African stuff, but I've heard good things about it. I just bought 900 rounds of it from a buddy, though, so I should know more soon.
I also have 500 rounds of the LC from Ammoman that arrived a few weeks ago. I haven't shot any, yet. It looks pretty good, but not great. I haven't observed any major problems with the LC from Ammoman, but I did notice that the bullet seating depths varied quite a bit. On some, the cannelure was almost completely outside the case mouth, on some it was completely hidden, and on others it was somewhere in between those extremes. It is loose-packed, and the headstamps are a mix of 02, 03 and 04. Loose-pack generally means it is from a lot that failed QC inspection. IIRC, the best lots go to the troops in the field. The second best still get boxed but are used for training. The stuff that fails both levels gets loose packed and finds its way into the surplus market.
My favorite so far has been Portuguese surplus. Unfortunately, I'm down to my last 100 rounds of it, so I'll be shooting the South African and LC soon.