Based on personal preference, I would recommend the sniper types, which are good at long range play. I like to think, that if I can shoot whoever is coming at me before they get here, then I don't need to risk getting hit when they come in range to fire back. Most of the time, this works (although only against sprayers, and amateur snipers), but this is only beneficial when played in a long playing field, or one with no more than 1 main entrance to a main room.
When you are required to rush, or breach a building, it is better to use your side arm instead of sniper, unless you are skilled enough to fire at a moving target while scoping. Warning though, scoping is the only way to accurately shoot at an opponent while using a sniper and when used in close range may be too highly magnified to get a good shot. A good sidearm (in combination with sniper) which I find quite useful when is close range combat is the Remington shotgun. Since this gun has a very high powered shot (higher than all other secondary hand guns, or shotguns) it will usually take care of an opponent with one shot, even before they can drop one bullet on you.
Since a sniper is usually one shot one kill (unless you hit an opponent in the leg, or they are wearing heavy armour) the recoil should not pose as a problem, unless you tend to miss an opponent more than you hit them, in this case, switching to a machine gun would benefit you more. The recoil can get very annoying at times, and a player can get impatient and waste an entire clip without hitting anyone - a tip for player experiencing more recoil than they prefer - is shooting at an opponent and quickly un-scoping and scoping again, this allows the player to aim more freely.
Clip size is something to take seriously- mostly because of the very long reloading time (which could take up to 10 seconds) and a lot can happen in 10 seconds. Different sniper models have different clip sizes, such as the PSG-1 which has one of the smallest clips of 5 bullets which can prove very critical when you're on a kill streak, and when you're the last person on your team. I have encountered many times in which I eluded an opponent, and they ended up using all their bullets in that clip, which automatically started to reload, and I picked them off with only 1 shot.



The pictures above show the 2 earliest snipers available to the player of Soldier Front, and the most powerful shotgun in the game (which I recommend in combination with the snipers) the top left is the PSG-1 sniper rifle, with a clip size of 5 bullets and high power, it is a 1 shot 1 kill weapon assuming you hit the target in the torso, the FR-F2 is the sniper on the top right which also is a 1 shot 1 kill weapon, but instead of 5 bullets, it has a 10 bullet cartridge, the main noticeable differences between this gun and the PSG-1 is that it is not a semi automatic (which means after each shot, the player un scopes, buts a new bullet into the chamber and scopes again to shoot), the other difference is the weight, which means you run slower when equipping the gun. The Remington M870 shotgun is the most powerful secondary gun, which can cover a large area of space while doing lots of damage.
Hope this helps; come back for more weapon info about machine guns, hybrids, grenades and items choices.