Grant, I have personally tried the Autoformers in my system. Used them with the Coincidents, on my Atma Sphere M60s. Three of us were using them at the same time, one of the people being a person who was widely featured on the site. A member of my audio group tried them later in his system.
As I was given my pair, my idol who was also given a pair to try announced, "I am adamant about the need for a transfomer in the amplifier - loudspeaker chain." Imagine how sheepish I felt as we convened two weeks later, with me having to say, "I'm sorry, they simply didn't work for me. The autoformers utterly destroyed the sound."
In the end, the conclusion of the four of us is that the Autoformers will NEVER be in our systems ever again. They simply rob all of the beauty and magic from the music. I see many on the audio sites recommending them as solutions all the time. Even if I don't participate in a particular thread, my answer is, you need to either buy a more sympathetic loudspeaker (often the best solution) or a more powerful amplifier.
All this being the case, I know of no one outside of Atma Sphere who has done more for the mark than Paul Speltz. He is a creative genius, as well as a seemingly fantastic and generous individual. I hope to one day try the Anti -Cables. I simply feel the Autoformers are a fantastic idea that somehow doesn't work for the die hard music lover/audiophile.