How far have power conditioners evolved?

I currently have an Audioprism Foundation III and like it. I run my amp directly to the wall. Are the newer conditioners that much better? Say, for instance, the Audience aR6 or one of the new power regenerators?
I would say they are pretty much the same as they have been.
The various types have proponents, and detractors. Same as ever.
I think they have improved considerably but the results you will get vary so much with individual conditions that it is hard to predict if you will hear a difference between newer and older. You may or may not need one depending on your AC quality.
i think it is necessary to distinguish between parallel and serial conditioners.

i have experiemente with active and passive conditioners in which components do not make direct contact with the conditioner. there are two types. the first is something which plugs directly into an outlet the other is a product that cois placed somewhere on the component. the latter are more recent in development and may use materials which were not used , say during the 90's.

as stan connotes, their effectives is not predictable. sometimes it is worth the time to try them.

quality of ac and your general satisfaction with the sound of your stereo system are salient factors.

notice, i have excluded serial conditioners, ie.e, those which interface both the component and the wall outlet.

there are so many of them it's impossible to recommend one, assuming you need one.
Same as ever? Elizabeth, such a statement implies either your system lacks resolution to hear the benefits of some of the great PC units out there, or you have not tried them. But they are hardly the same as ever.

Many must be tried to determine if one brings on an improvement to the system. Some can and do make a huge difference to many systems, even those with dedicated lines such as mine.

People that have only tried a few or budget-priced units should not make blanket statements about the performance or relevance of PCs.
My AudioPrism Foundation III definitely makes a nice improvement. As I said earlier, I don't plug my amp into it as it decreased the dynamics. I live in an old building in San Francisco which is right across the street from a hospital. I'm fairly certain my power isn't the best.
Try the Synergistic Research Tesla Powercell SE; you'll be using your other power conditioner as a door stop! Anyone I know that has tried it has purchased it. I owned the Audience 12T with top of the line power cord; it's a great unit. When I heard the Synergistic Research I was floored. Add the Speaker cells and you'll be even more pleased. Demo one before you buy anything; you will not be disappointed.
Like anything else line conditioners have advanced. But at the same time it seems that there are probably just as many line conditioners not worth owning today as there was 5 or 6 years ago.

In other words, finding proper line conditioning has always been like finding a needle in a haystack. But it seems there's a few more needles today.

When discussing line conditioning I always insert the word proper with the intention of implying there are plenty of improper line conditioners out there that give the entire line conditioning segment in general a very bad name. Many try improper line conditioners and then say it didn't work for them and since line conditioning failed for them, therefore all line conditioners must be snake oil.

There are fundamentals to proper line conditioning (lc) and failing at any one of these should with few exceptions generally be enough to stay clear:

1) Induce no sonic harm of its own. This eliminates many lcs right there.

2) The LC should be passive so that it draws little or no current of its own so as to not rob a thirsty amp of the juice required for dyanmic/complex passages.

3) It should be dedicated one per component.

4) It should filter/condition bi-directionally. Particularly for digital source users since digital components induce digital noise and digital noise is bi-direcitonal implying that the noise goes back into the wall, even back to the service panel and then induces sonic harm into other components.

5) It should actually improve the sound since that is its purpose for being. Again, many fail here.

Once you've become accustomed to listening to a system employing proper line conditioning you will no longer any system for longer than maybe 10 or 20 minutes before you have to leave the room from ear fatigue.

Those unfamiliar with proper line conditioning should keep researching. It's there, they exist, and the problems of dirty AC, which everybody has to one bad degree or another, don't go away simply because one denies its existance or claims that it only happens to people in other neighborhoods.

One note of caution. Some of the most popular line conditioners (biggest sellers) are often times some of the worst performers available. Again, these inferior products harm the entire segment.

As for me, for 10 years I've been using the lesser known brand Foundation Research starting with their early models where I think every reviewer who reviewed them bought the samples to the latest version that's been out for about 5 years now which are multiple times better than the early versions.

I've gone over to friend's homes where we've unplugged their very popular and expensive line conditioners and their systems sounded much better just plugging the components directly into the wall. Then we plug in my LCs and it's soooo much more musical.

What's sad is people sitll have yet to understand that proper line conditioning is an absolute foundational requirement to proper system building.