So the Exotic titan helmet provides Unstoppable for free. Cool. But it doesn't give the benefit that titans look for in choosing the perk node and that is the Armor boost. Unstoppable is pretty useless without the armor boost because Fist of Havoc is "leap-slam-done!" Besides a perfectly timed sniper round, nothing kills a striker mid-slam without unstoppable. At least boost the radius damage radius or give a split second to slam again.