Pros:

Reminds me of the original Left 4 Dead M16.(which I like)
Really fits great with the animations.
Would recommend these animations to anyone who personally likes the M16.
Makes my hands feel more at home.
Great for killing.

Cons:

When putting the clip in, I think slapping the gun and then continuing to open fire is kinda old and corny, but I won't take that much points off for that...

Conclusion:

Great Gun, Animations, and look. I will definitely use this gun for a LONG time...