Even for Koga AM3, I probably wouldn't bother with crit. I'm cheap, number one, and DA Otronif are useful with weapons other than Koga as well.
For the Otronif pieces in the OP, what augments are primarily desired? Coming from MNK, a few pieces have crit rate and a few have DA, so I'm curious as to which are superior for SAM.
DA is going to be your best choice. I know some people who have gone for accuracy and used them in hybrid sets, since they offer Store TP and DT (for the 119s).