I don't know whether it helps or not, but I can't shooting with it :P I don't like it.
I think the m4 does sligtly more damage with the silencer on. I tried it once, I shot at an afk with and without the silencer and noticed the health bar :P
But I'm not 100 % sure
With Silencer- Less recoil, minus damage, little noise.
Without Silencer- More recoil, more damage, more noise.
I use without it.
The M4A1 does more damage without the silencer.
I use silencer while spamming, as i can hear the "dink", if any(ofc at close range).
I'm not sure about this, I read it somewhere on hltv.org i think but anyway...
Silencer - More damage on short range, little noise
No silencer - More damage on long range, lots of noise
I think the recoil differs a bit too but i'm not completely sure, this info may just be bullshit so don't take me to seriously :P
Silencer - little noise
No silencer - lots of noise
its same with or without it.