The FAMAS and MTAR21 ruled Vegas, they both had very high rates of fire and the same amount of damage per bullet as the rest of the assault rifles, even though the AK-47, G3KA4, and SCAR-H shot much larger bullets. The FAMAS and MTAR21 were also much easier to control than the other assault rifles that shot the same bullets. We have not used these guns in the game yet, but we can make conclusions from watching the New Weapons trailer here. http://www.gametrailers.com/player/30990.html
The MTAR and the FAMAS didn't dominate Vegas 1 completely they just dominated the other assault rifles. A good shot with an MP7 can smash a FAMAS or MTAR user in the head before they can get their full clip off. I see your point though, they were great guns in the game..
In vegas 1 you could use any weapon effectively so there was no dominating weapon. The Famas and Tar were just a little bit better and thats why everyone used them.
In real life, the weapons deal great damage and have outstanding firepower. The bullpup design of the weapon is why the two are powerful, shortened design with all the components to the rear means more accuracy. Having that much of a controlled accuracy means you can deal more bullets to a target, meaning that you could increase the rate of fire of the weapon to match the accuracy of a standard assault rifle.
In my opinion, keep them the way they are. All the weapons in the assault class are perfectly balanced.
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