The PoE weapons should be re-rollable with the random "burns" & fallen targeted perks. They aren't like raid or trials weapons that receive the exact same perks. Sure the first perk is always the same & I don't know how it would affect elemental primaries from PoE, but having something like Shank burn take up a whole perk slot on an endgame weapon (not just an extra slot like the VoG & Crota weapons) is a step backwards for endgame loot.