The odds on doing this must be insane. For how infrequently the heroic items drop and I get 2 dups.
I've gotten a heroic bazooka, and a heroic f'ing machine pistol.
I also have pretty much every "epic" Type 100 there is.
The only decent Epic guns I have an an M1 Garande and an SVT.
I get mostly dups now except the endless amount of pistol grip designs.