Power Pipe Really Work?

Looking at a 60"-72" long 2" power pipe hooked up to my shower only in a wall on the first floor between the shower on second floor and basement where the boiler is.

Does the thing really work as advertised? http://www.renewability.com/general/residential.html

We have 4-5 people showering every day. Installing a Viessmann oil VR1-22 and Superstor 45 gallon indirect soon.

Or is there better ways to save oil? Also insulating all the hot pipes I can access.

Posted here because this is the busiest forum.

http://www.renewability.com/uploads/documents/en/backgrounder.pdf

Your shower water will be 120 degrees or less and that will only be while the water is running. I cannot imagine a "40% savings" given the limited amount of heat transfer area in the actual device, and the inequality of the velocities of the pressurized water and the gravity drain..