I've never seen a recommended build which includes Essence Reaver on Ashe, but I can't work out why.
80 AD, 10% life steal, 10% CDR plus the mana regen means you can leave her Q on permanently during teamfights... why isn't it a perfect item for Ashe?
I understand it's not the best first item, as Infinity Edge makes sense with her passive, but for mid-game sustain and perma-Q teamfights, I'm not sure what I'm missing that means it's not worthwhile.
So why not Essence Reaver on Ashe? What are the drawbacks, or is it simply that other items are more effective?