The output shown in the right graph is lower, especially the harmonics of the incoming 60Hz. This demonstrates the Power Plant is doing what it claims to accomplish.
Critics however maintain the high frequency noise should not be present, assert this noise indicates the Power Plant is not a “real” regenerator, and opine the Power Plant does not do anything meaningful.
It truly comes down to whether one hears an improvement in their system while using a Power Plant. Of course, if you do not hear an improvement, send it back. Or, like @NordicDave you may be blown away as he stated in his thread, Just Bought a Regenerator - WOW :