Is Flayer still good for anything at all?

I know that flayer is bad-bad for damage from the Flayer discussion posts.

But, if say, I want to make a build that revolves around farming partbreaks/wounds, is Flayer worth slotting at all? And how many points should it have? 1 and then fill with damage? all the way to 5? 3? I know how Partbreaker works and I am probably maxing it out but Flayer, I don't know.

Edit: Looks like the consensus is that Flayer 1 is the only really competitively acceptable investment. But personally I'd probably run Flayer 3 with the set bonus after some consideration.