If you need help figuring that out let me know.
My results (Wspeed = 568.50):
Without secondary stats:
iLv 516 DPS: 40152.18
iLv 502 DPS (Zerat RF): 35218.80
Fun fact: Even adding the secondary stats (including gems) to Zerat, the DPS is still only about 41.1k DPS, about 1k better than a 516 without secondary stats added in.
Obviously the Weapon DPS/strength differences make the difference. At least until you get a 522+, where there would be no contest.
But, hopefully I get a 522 this next week's run so I don't have to worry about this shit.