Anyone have the Answer?

Your AC line measures from the back of the device it is connected to all the way to the power station that generated it and includes any substations along the way.  All of it, the entire distance, picks up EMI and RFI.
I used Tripplite for many years in both the 4  and 6 plug models and for awhile the Isolation Transformer models.  I considered the Surge Suppression mandatory as I live in Miami and we get lots of summer thunderstorms. ..  and I actually lost two self-powered subs to surges.
I recently decided to finish off the system I have been building from time to time over the last 30 years and decided to add a high-end power conditioning system.  I had reasonable beliefs it would be helpful since I can hear a difference in background grain from summer when all AC units are running in the 167 unit building and a cool winter day when few or none are.  The power lines are also noise polluted by refrigerator compressors, computers, florescent lights and so forth specifically including lots of RFI from broadcast stations.
I purchased an Audioquest Niagara 3000 and a Monsoon power cord for it, and upgraded all the other power cords in the system to Audioquest noise drain types compatible with current requirements and the 3000. 

It absolutely has made a difference in background blackness, noise and grain in the sound and other areas but I would say this..  if the resolution of your system isn't at a level that you can hear differences in different interconnects, tubes and power cords look for improvements in other places first since you are still baking your cake and it's not time to put the icing on yet.

Try this: find a dealer who will let you audition one of those really pricy power cords. If the cord makes a noticeable improvement, your power is dirty and a "machine" will help. Good Luck!

I'll stick to my 4 26,000 mf filter caps per channel, per 100 watts times six (3 amps).

@chorus 
Your question is very straightforward and I certainly understand why you asked it.
Unfortunately, certain users on this site feel like they own it and that they can deride people if a question is not worthy of their response. My guess is that no one will put up with their behaviour in the real world, so they troll this site trying to feed their egos. They usually know what they are talking about, but instead of helping people that know less than they do, they choose to mock them for their perceived ignorance. Luckily, there are many decent people here as well, as is illustrated by the number of actual attempts to help find an answer to your question. And, thanks for asking the question. I was wondering the same thing.

Surge protection won't stop Lightning strikes that's why you have insurance. For normal surges the best thing is have the electric company put a device beside the meter, next best is have an electrician put one in the panel box.