How good is the new wildfire surge inner way for the heng blade build?

It seems to provide dmg buff,dmg reduction and 2% HP drain (life steal?) of your max HP? It seems too good to be true yet nobody mentions it in their guides? I’m still a noob so I appreciate the survivability in a innerway. If it’s not as good as it seems, what other innerway would be a good survivability option for the 4th slot? I’m using morale Chant, frostclad knight and throat piercing art. For the gear sets I’m using the recommended stone split strength set. Should I be changing anything?