PC on Rare Chaos Axe with 20%below50

Gold Chaos Axe
dmg 6~28
req.8
+20%dmg when health below 50%

Since the War SF/GF run builds used Grenth's balance, this mods(20 below 50) become more and more popular.
I just wonder how much it worth now?

Does anyone give me a hand for pc this axe?