Non-Official Platoon.
Weapons have been classified as of their use in all ranges. To be preferred after looking at the following order.

Sidearms - .44 Magnum > MP412 REX > M93 > MP443 Tactical Light > MP443 Suppressed > G18 Suppressed > G17C Suppressed

Assault - AN-94 > M16A3 > AEK-971. (Heavy Barrel )
Support - M249 > M240B

Engineer - M4A1 > A-91 > SCAR-H (Heavy Barrel)

Recon - M98B > M40A5 > SV98
MK11 MOD 0 > M39 EMR

As lots of assault class tutorials present, I found this weapon hasn't been justified properly.
Here is why.
http://ignite-esports.com/forum/topic/1694-an-94-usage-tutorial/#entry5970

BF3 placed in your arms.

Tutorials - https://www.youtube.com/playlist?list=PLLiTWRtHiTfkHV_OVC3xfqXRU1bkEfoj9

https://www.youtube.com/watch?v=JsWf87BfIX8

https://www.youtube.com/watch?v=YyEMioH3aE4

Gameplays -
https://www.youtube.com/watch?v=PS9wWPlAvko
https://www.youtube.com/watch?v=5Sxv3FnDFbQ