Think about it for 5 seconds. With the aclyophage helmet you get 4x golden gun damage which you can spread around as you please. The nighthawk grants an extra 2x damage in one shot plus a meh perk of keyhole. The only time I'm gonna use it is for a solar burn nightfall boss. This is simple math Edit: the extra 2x damage I mentioned was in comparison to using the aclyophage. I'm aware it does 6x the damage of 1 golden gun shot