QUOTE(Epion @ Nov 27 2015, 16:21)

Tried my
DW with magnificent ethereal axe of slaughter (void / dark) and legendary rapier of balance (cold/void)
versus my
Niten with legendary katana of balance (holy / void) and magnificent ethereal waki of slaughter (void / dark)
I thought DW would have been faster, for many reassons.
How wrong i was...
I have close to the same set-up as you. Leg Hallowed Club Slaughter + Mag Rapier of Nimble vs Mag Fiery Kat of Balance + Mag Ethereal Waki of Nimble
Mind you, this is at lower difficulties, where the effects of Domino Strike + Bleeding Wound pile up a lot quicker than Piercing Wound, even against the schoolgirls. At higher difficulties on non-SG arenas DW is still much quicker for me. While my Evade + Parry multiplies out to just about the same on both sets, DW has the benefit of Stun and a far higher attack damage killing most monsters outright with the Orbital Friendship Cannon. And at the current moment I would never use Niten on high-difficulty SG thanks to the insane amount of SG hp.
Getting a decent Katana of Slaughter and upgrading my 2H prof (260 vs up-to-level DW prof) would give me a better time still and maybe match DW at higher difficulties.