Personally I love the AK-47. I went from the M4 which I weren't as good with, to killing people on a daily with the AK. I think it's more or less what you prefer.
I'd test the guns out at the shooting range, then test them out on real people (raiding, robbing the bank etc.)
Accuracy, no recoil when spraying while crouching, cheap, doesn't stick too far out of your back when carrying, amazing fire rate which is just made for close quarters. Absolute beast.
Only downsight of it are the ironsights of it though but that will be fixed in the weapon update.
I like the Famas because when I'm being all gangster like Tsotsi then I can refer to my peers as Famas'.
Like I'll be like "yeah that sounds good Fam" but put the "as" at the end of it to sound hipster with my ice-coffee.
For me it's the M4 but everyone has chosen it already so I cant repeat the obvious...
AK-74u
Cheap, hard to notice on your back, high fire rate and reasonable recoil. It uses the popular 5.56x39 round which is a blast to shoot ingame and IRL. It isnt the most silent gun out there but hey, we've seen louder guns like the AK-101. Attatch a compensator, red dot sight and a deafult stock and you have yourself a killing machine that, for 11k price, is more than worth it.