Submachine gun: MSMC with Long Barrel, Extended Clip, Quickdraw. Perks: Lightweight, Toughness, Dexterity perk 3 greed Extreme Conditioning. And a Kap 40 unless your playing SnD then take off the dexterity and put the extreme conditioning and then a DSr secondary

 

I ran

AN-94
Stock, Suppressor, Quickdraw

Perks:
Ghost, Lightweight
Toughness
Dexterity

Wild Cards
Primary Gunfighter
Perk 1 greed

Worked well with the slaying Orbital VSAT, Dogs, Swarm setup and the more defensive / supportive Counter UAV, Orbital, EMP setup. Then again, it works well with any scorestreak setup. The only thing that can truly beat the AN-94 is the M8A1 (I'm not including shotguns in close quarters, because that's an obvious loss). I hated that gun with every atom in my body.