I have the Equi=Tech 10kva & have found it to be better than anything I have used to date.
I have tried & used many of the stand alone units as well as some of the power regeneration. The results with the Equi=tech's unit is way above the rest. IMHO....of course.
Some of the stand alone units work very well & are worthy of consideration depending on your budget & needs.
Maybe one of the unimpressive results stated above is due to lack of burn in time. I would say with all the new wiring, transformer, & outlets it does take some time to settle in for the true evaluation of the units. In my situation & system I have to agree with Mike Lavigne, the equi=tech was the way to go. Mine has been in service for 3+ years & I could not be more pleased with the results.
You do not have to buy the mack daddy Equi=tech unit from them to get great results. Call & talk with them, they are very knowledgeable & helpful to guide you. They have been doing this for many years & have a great reputation in the industry.
There are many ways to go about cleaning up your power & it's very hard to say what works the best. Many factors play into the equation, where you live & the power grid around you is a factor. Doing something to help YOUR power grid is always the first & proper step to take in achieving good sound quality for your room & system.
Products are always improving, so who's to say what is best.
Do your homework & make a educated decision on what works best for you & your budget.