The mg08...just wtf is this gun. It's not a proper LMG or SMG. Its literally the worst gun however you categorized it. Any support gun is better than it and any current assault SMG is better than it.
The double barrel shot gun is a total joke. Why would you even use it over the current shotguns. Even the 12g is better. Having to reload after every shot you're basically hoping that you kill that person on the first shot and there's noone else behind him. Also, I feel the pallet spread is wider than the sawed off shotgun that's already in the game, so I even prefer teh sawed off shotgun over it.