Here is my three favorite class set ups for this game so far, keep in mind I use each one for a different reason.
Core Games Modes
primary -AK-47 w/ Suppressor and Dual Magazines
secondary -Strela-3
lethal -Semtex
non-lethal -Nova Gas
gear -Claymore
perk 1 -Ghost Pro/Hardline Pro
perk 2 -Warlord Pro
perk 3 -Hacker Pro
Hardcore Games Modes
primary -M16 w/ Suppressor and ACOG Sight
secondary -Strela-3
lethal -Semtex
non-lethal -Nova Gas
gear -Claymore
perk 1 -Ghost Pro
perk 2 -Warlord Pro
perk 3 -Hacker Pro
Fucking Around Class
primary -Stakeout w/ Grip
secondary -Crossbow
lethal -Semtex
non-lethal -Concussion
gear -C4
perk 1 -Ghost Pro
perk 2 -Steady Aim Pro
perk 3 -Hacker Pro
Kill Streaks
Care Package
Sentry Gun
Rolling Thunder