Watch the videos on major malfunctions website and see for yourself. I think they are pretty quiet. The Tac-65 I have on my P22 is great. Quiet as heck with sonic, and even quieter with subsonic. I don't think Hollywood quiet really exists. JMHO.
Hollywood quiet exists with standard velocity .22 out of a boltgun. I've also expierenced close to HW with a singleshot and subsonic ammo in a .308.