I didn't test this memory well, I've just set AsRock profile for 2600 or 2666MHz, don't remember exactly and tried to find max frequency with main timings and wcl, and it was Z87 board, not z97. If I have possibility to restes this memory I would do, but I have only z77 with 3570k. And this cpu doesn't like psc at 2600 or higher.
for 2400 AsRock profile Vdimm is a bit lower than 1.65V, websmile said to me that it is good.