I have actually went away from using them so much on this prestige. Look, I don't know stats by numbers regarding effectiveness of weapons and attachments like so many do, all I know is that seemingly, I get better results without them on most game types.
True it does, but the benefits I think outweigh the costs, which is what I've been trying to say the whole time. Pros: stay off the radar, reduced flash. Cons: Less range (which affects the overall damge).
The only benefit is for stealth players. I use suppressor on my SMG class most of the time, a lot easier to sneak behind enemy lines. And you do lose a lot of damage over range which makes SMG even more CQB. I think rapid fire is overpowered on SMGs because they already have a high RPM.