Regulators don't affect efficiency, they affect consistency. All the regulator does is make sure your gun gets the right amount of pressure to operate and fire a ball at the same speed each time, it doesn't affect how much air your gun actually operates off of.
This line is in remembrance of the 2001 terrorist attack on the United States of America, this day of September 11, 2001.
If you're tired of people putting lines in their sigs and trying to get you to put it in yours, don't put this in your sig.
"Accuracy by volume is still accuracy nonetheless."