PS Audio Power Plant vs EP-2050?

The EP-2050 does work as a waveform corrector and as a surge protector.  I've tried the Power Plant, I plan on trying the EP-2050 next.  Many reviews are positive on the EP-2050, including:

"Examination of my house's line voltage on an oscilloscope revealed a smoother, cleaner 60Hz signal than before."

I am listening to my system with preamp, disc player, disc player power supply and phono preamp running off of a PS Audio Premier Power Plant.  After reading about the waveform corrector I didn't see anything about it lowering the harmonic distortion as the PS unit does. The website description addresses surge protection.

Not sure I would be thrilled with "20dB/decade rolloff above 2.5kHz" for feeding an audio system..

Interesting item though and I am by no means an expert on the EP device.  Perhaps someone with more electrical theory knowledge will weigh in.