Shawn,

If your standard silencer was in standard form, i.e. with the baffle in place, you would notice a 300-400 RPM change, as you would if you removed the baffle from the standard silencer. In addition, the Mac's one piece weighs less then the standard silencer. If you fly a light 3-D model, you would notice, but it is in my first post.

Even Mac's themselves don't claim any power gain. They have full length tuned pipes that can realize real gains in power.

The original un-baffled silencer and the Mac's one piece are within about 100 RPM on most props.
This difference will be maintained if you drilled the exit hole larger on both.

Real power is made with products that are intended to make it and not in all case. It is not made with products not claimed to make more power.

See Jett, Nelson and other Performance products manufacturers' advertisements.