Yes and no.
Ruin Wings, [i]when they work[/i], is incredibly powerful. As you said, Gjallarhorn for days. [i]When they work[/i].
The problem is that you're just as likely to hit a dry spell where you don't see [i]any[/i] heavy ammo drop.
Ruin Wings are very feast or famine.
English
-
yeah, no other item in the game directly modifies an ammo type both it's probability of dropping and how much you get. Even if you get a few drops it is more efficient because it has Surplus imbedded in with the perk, and it stacks with the weapon variant of surplus.
-
Not many people actually realize you get more ammo per box. Most just assume they aren't working when heavy ammo isn't literally coating the ground. I tried to explain to someone once that the main focus of the perk is more ammo per box overall, but they were arguing the perk only increases ammo drops and that I don't know anything.