Don't listen to R2, he's senile. The VTAC is awesome.
When your ready to suppress, look into an adjustable gb, and possibly a new charging handle (I don't remember which one you have).
The PRI M84 Gas Buster charging handle is designed for suppressed rifles... but it's big and bulky, not ambi, and costs $90. The MechArmor TacOps-1 has tighter tolerances that make it suitable for suppressed fire. It's also big and bulky, but it IS ambi and is free when you buy a MechArmor trigger (check out our promo). Just sayin...