X3 Knife
RS8 Pistol OR D49 Revolver
MRS138 Tactical Shotgun OR one of the pistols listed above
SRS900 Battle Rifle OR R78A1 Sniper Rifle
Pineapples
As for the Shyke's questions, the AM67 Assault Pistol (the snub pistol that you are probably referring) to is incredibly overpowered. It easily does twice the damage as the M806 Pistol (the .45), has higher clip capacity, higher rate of fire, and that flash thing that's easily more useful than the laser sights on other pistols.
As for the machine guns, the M353 is also somewhat overpowered in my opinion. Very easy to run and gun with it, and you can't go wrong with a 100 round ammo belt. The M925 just has too low of a firing rate to feel "right" to me as a machine gun.
The M50 has that grenade launcher which is pretty useful. Rather small blast radius though.
The Battle Rifle can be used as both a "Sniper Lite" and and an Assault rifle, and is pretty good at both, with very low recoil (ignore the recoil animation and look only at the shot placement) and relatively low movement accuracy penalties.
The revolver is just cool. Highest damage of any of the pistols, albeit with an incredibly long reload time. The AM67 is still much more effective though
