Has anyone else discovered the delights of the PP90M1? I use that with akimbo FMG's as a secondary - they are so deadly, you could use them as a primary!
Also, the specialist strike package is amazing! I've found a brilliant set-up where i use hardline as one of my main 3 perks. This way, if i get just 1 kill, i have 4 perks, 3 kills gives me 5 perks, 5 kills for 6 perks, and if i get a 7 kill streak i have EVERY perk in the game at once! It's great fun! You are fast, can ADS quickly, can reload quickly, can't be detected by UAV's or air support, you have extra explosive resistance, you can see all enemy equipment, you have better hip-fire aim, you can strafe quickly whilst aiming down sight, you pick up ammo from dead bodies, you are completely silent when you move... ALL AT ONCE!
Loving it.