This is not a hybrid weapon and it is legit. So no bank safe-keeping. There are two versions of the Cobra that you can find. The Skookum and Tumtum with the extra Critical effect bet less dps.
There is a debate in the gearbox forums of which has the better dps after all (critical accounted also) and it ends up that Skookum is better since the EXP element has already the high critical chance in there.
And some more info about the cobra. It turns out to be legitimate after all (and not a lab creation), and the devs made a mistake that they openly admitted at the forums. They drop not from any BOSS in the DLC but from the Burners (every version of them) and the better place to farm them is the Beatdown. BUT they didn't do their math correctly, and it only has a 0.88% chance for every sniper the burners drop. So they have to drop ~115 snipers for you to get a Cobra. That means a veryyyyyyyyy looooooong farming[COLOR="Silver"]