Team death match/HQ/Domination: P90 with Bandolier,Stopping power, and Steady aim
Search and Destroy/team tatical: P90 with Silencer,Uav jammer,steady aim
Free for all: Any gun any perk that i wanna train
Sabotage: Anything with extreme condition
When i don't have my p90 i use a m16 with the same thing or with double tap.
Why p90 or m16? I am sure to die anyways so i rush in with my p90 and if someone surprises me i have my steady aim so i wont need to look down range and my m16 is power full and can take down an enemy with at least one trigger pull. (M16 is the 3 shots per trigger gun and P90 is the crazy gun that sprays all around when holding the trigger)
Some times i snipe so i just go with the m40 or the Barret when it is available, i use the perks Claymore/Bandolier,Stopping power, and iron lungs/ext condition M40 and Barret with stopping power is 1 hit kill it might need 2 shots though if the enemy has juggernaut.
In shipment i like to use a shot gun, i personally think any perk is good well i use Grip,Stopping power, and steady aim (Grip gives accuracy Stopping power assures 1 hit kill and steady aim is because i will never look down range).
When i wanna go crazy or im just lazy i use my uzi with any perk, uzi is like the p90 but scatters even more.