Most raid mobs have strike through, unless something has changed. I parsed it out with a few SKs during CoV and the decision was that the “riposte” argument for hDex tanking didn’t quite stack up. Now, that’s not to say there aren’t other valid arguments for running hDex - I have three tanks (one hSta, two hDex), and my personal experience says that busting a proper meat shield with over 850k hp is just super helpful.
Now, to the original question: Mages should go hSta. Mod rods = hp. You should be hitting multiple rods during raids. Multiple rods = multiple hps going bai-bai. Plus AoE effects on raid bosses suck. Nothing like eating a few hundred thousand-point AE and a badly timed rod!