Power regeneration - good idea? PS audio?

A PS Audio regenerator is definitely something you simply must try in your own setup to determine if it's something for you.

Hearing results will depend on your homes power quality and how your setup responds to without and with one.

Some find it to be a waste of money, others like myself, actually "hear" overall improvement. 

No one here or the audio forums can give you solid advice on what's "best".

"Also since the P 15 is being used to re-create an electrical signal why would there be a need to attach it to the wall with a very expensive power cable?"

Definitely any "audio mystery" as to why we PP users  get the fancy cable to power it. I have all Nordost from the wall. The MSRP for the PC is nearly half the retail of my PPP! 

Reality at least to my ears-  aftermarket PC into the PP doesn't "improve" sonics.If it does, it is so subtle if anything. 

Even the PS Audio videos don't have a concrete answer as to why you should consider one- you just do it. 

Part of the audiophool protocol.

PP's are something to put on the list after you're convinced you did all the baseline essentials to dialing in SQ.

Dedicated line/decent receptacle before considering all the other madness.

Your alternative choice is "power conditioning" or whatever you want to call it, is another polarizing subject.

Audioquest Niagra and the like has their devotees.