What's better? (FA:S, TFA, CW 2.0 or M9K?)

I recommend you to use CW 2.0 because you can use special tools for your weapons.

Depends on the type of server CW 2.0 is good for darkRP but if youre gonna make a star wars RP server youre gonna need to use TFA

Personally I love the flexibility of CW 2.0, it reminds me a lot of how weapons in ArmA work.

CW 2.0 & FA:S are definetely go to's. Really realistic addons, with alot of interesting stuff.

I think a great pack of weapons is TFA, at the moment it is the most balanced and all Addons support it

M9K is definitely the best. It has the least amount of bugs and is most stable

It depends on what you want, if you want just a simple weapon pack then I would suggest going with M9K.
The other weapon packs include more as they have attachments and customization.

Best weapon mod tfa among them i have never seen better than it

m9k is too simple, look for a realistic addon unlike it