I just added this mod today. Hopefully ModDb will approve it and post it soon. I'm new to this site so please ignore my mistakes (extra posts, etc.).
One of the things that you will find that sets this mod apart is the realistic bullet penetration. Most bullets from handguns, shotguns, and submachine guns will just bounce off body armor like in real life. Notice I say most, though. Shoot a guy enough times with any weapon and you eventually kill him, unless he kills you first. So, I recommend using the suppressor and aim for the head. Hopefully by the time he finds you it will be too late for him. Guys who are good shots will like these guns still because they are so light. (Low weight = faster movement, but that's a subject for another post.)
Assault rifles and light machine guns are the opposite. Their bullets will go through sheetrock walls like they aren't even there. Overpenetration at close quarters now actually happens, but lay down enough fire and it won't be a problem. Two, heck three kills with one shot from a sniper's rifle is now possible. Just make sure you choose the right type of cover. The enemy's guns are just as powerful as yours.
So you choose. Be a tank, wear heavy armor, and lay down heavy fire, or be light and maneuverable and use tactics to your advantage. I hope you guys like the mod.