Purple Surfboard vs Sky Ski

Something that's been on my mind for a while is which of these weapons wins in terms of DPS for bossing. Some of these might not be true at all but this is what I've heard so far from a few sources or know about the 2 of em
PSB:
-5 Extra weapon attack
-Fast attack speed
-Pole arm crusher apparently faster attacking speed than spear crusher
Sky Ski:
-Normal attack speed
-30% (?) damage bonus cuz of spear crusher stab animation

Seems pretty clear sky ski would win when u hav a bucc in the pty but assuming there is none, can anyone tell me which is the better choice?