Go with the South African.
The Argentine stuff shoots "O.K," but it just looks soooo crappy.
I ran a bunch of the Arg, thru my M1A with no problem; average accuracy at 200 yards 2-3MOA).
Last batch of the Arg. I got was "loose," and brother, was it loose. Fulla sand, dirt, etc. Sat up all night getting the crud off.
SA is sealed in a battle pack!