It would be a really nice feature if you could be able to shoot and swim at the sametime or even float while shooting, with the advance technologies of the nanosuit I'm pretty sure it's possible.

Most guns will not fire under water. Plus underwater shooting would cause some serious camping. The last thing we need is a guy underwater just shooting everybody that walks by.

Yeah, plus there would a new calling, "shark noobs" lol

Yup, I say no to the guna firing in water. Water is for transport and drinking.... not shooting if you want to win a war.

Don't compare anything to Snake's skills, not even the Nanosuit:P