1) if you are just starting out, or if your dark grid is minimal, you should separate them and use them both.
2) if you have a decent dark grid, you will have no need for this weapon. Put both of them aside separately, and see what happens when CyGames decides to give the weapon 5-star. (Traditionally, CyGames has given Limited Series weapon a huge buff when they receive their 5-star.)
Not sure if any of the mods still support this community, but they should be aware that the forums are infested with bots and that their forum needs to be upgraded.