Just a quick question, can this weapon actually be used by companions? I've tried giving it to both of my rifle users, Vic and Skynet, but neither of them seem to want to unequip their standard Sniper Rifle.

Also, I love this weapon. Seriously.

Tell them to unequip their sniper rifles (if they refuse due to a bug take their .223 ammo away, so they can't use them any more) run and take them away from them. This should make them using the gauss rifles (are they loaded ?).

Relieving Vic of his sniper rifle entirely did the trick. It strikes me as odd that he would consider it a better weapon than the Gauss.

The gauss rifle isn't actually super-strong by itself, most of its killing power comes from the armor penetration and damage modifiers of the EC ammo it fires. Companions just look at the base damage of the weapon, which is why they'll usually prefer the slower 6AP sniper rifle to most other weapons.