I own both but would have to recommend the Domino. Ymmv though. The reasons being that I prefer the nice and thin ffg blade on the domino. The flipping action is better on my domino than the southard. Normally that's not a reason I would include but since you mentioned it above I thought I would throw that in. Of course, it could just be the southard I own that doesn't flip so well. Then there is the ergos. The domino is probably one of the most comfortable knives I own. It's like a more refined manix. The southard on the other hand is downright uncomfortable (for me). I own the blue domino so the steel is the same on both models, and yes I prefer the blue G10 over the cubic carbon fiber of the original.
But like I said, ymmv.
Most recently acquired: Paramilitary 2 Tanto, YoJUMBO, Swayback, Siren, DLC Yojimbo 2, Native Chief, Shaman S90V, Para 3 LW, Ikuchi, UKPK, Smock, SUBVERT, Amalgam, Para 3 CTS-XHP, Kapara, Paramilitary 2 M390
Grail Paramilitary 2 M390 X 2! ACHIEVED!!
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