Now that the game is out, and I have been using more weapons:
It's hard to pick just one, they are all really good.
Started using the AEK, like that one too, I like any gun I use.
i like the M39 EMR( unlocked in co-op)
UMP-45 is really good
870MCS is great for up-close-and-personal encounters
SCAR is best carbine ive used so far
R93 is the best sidearm you could have. fires so fast, holds 21 rounds, can go from 3 round burst to semi-auto
i could go on and on
The difference between the TTK in the weapons is smaller than the average human reaction time. Your reaction time will determine how well you play, not which gun you are using.
A good player using one of the worst guns will always beat a bad player using one of the best.
The UMP and SCAR-H are pretty hard to hang around however a UMP should be weak as hell due to the fact it uses 9-19mm rounds,the top contenders for best damage should be rifles that use 7.62 rouns such as the AK family and LMGs like the 240B,M60E4 and the PKP.UMP,PP 2000 and F2000 need nerfing,I've used those 3 and found them to kill 90% of the time in 3 shots at the body O.o,way to quick.M27 ALL DAY >>