Audioquest Niagara 700 vs. PS Audio PowerPlant 20

I have the Niagara 7000 and really can't say anything bad about it, but I'm intrigued by the PS Audio P20.
What I like about it in theory is that it makes clean power from what it's given from the grid, where the Niagara simply filters the power.  Michael Fremer wrote about his issues with the power feeding his home in a recent Stereophile, which is what got me thinking about this topic.
I'd be very interested to hear from anyone here who has compared these two components and would like to share their findings.  
Thank you in advance!
Thanks for posting the review/comparison.  
It's a good write-up, but it seems obvious that he is being very careful to not say anything negative about either unit.  Not that I would expect much negative to be said about these brands, but I would have liked him to declare a winner, or at least a preference for one or the other.  
That said, I have no compelling reason to make a change from my Niagara 7000 at this time, and given how close they came to each other in performance, I found the article useful.  
I believe I have read on two occasions people I would consider as
competent saying they felt the 7000 was better than the PS 20.

Better wait for Fremer to finish his review.

I wish he had the Everest by Shuyata for a trial also.

I am so waiting for a proper comparison of these power conditioners, where someone comes out and calls one of them the king of the hill.