In the name of full disclosure, I am Jules Coleman and I have reviewed the Silverback at www.6moons.com. I purchased the review pair, and just happened to me perusing this site to see what others thought about the Silverback when I came upon this thread.
Unlike some other speakers, the Silverback are not likely to overwhelm you with a casual listen. Everything is in balance and quite relaxed and composed. But you will find that not only is this an attractive feature of them over time, but it means that you will hear what you put in front of them. There is nothing particularly showy about them. If anything, they are designed to showcase the music and the musical chain that precedes them.
I drive them with a quite powerful 8 watt monoblock amplifier; I have heard them run quite successfully in average sized rooms with 10 watts. I have reason to believe that John DeVore voices them with tube amplifiers. Among tube amplifiers, I would suggest highly resolving and well balanced tubes. I would stay away from overly rounded, ripe or fat sounding tubes. You'll be missing too much of what the speakers can provide.
Though the speakers are visually unprepossessing, they are quite handsome I think and are clear technical achievements. There is a lot of sophisticated design and engineering involved, but all of it in service of the music. At least that has been my experience.
There are lots of very good speakers -- dynamic and otherwise -- and listeners look for different things from their speakers.
The Silverback suit me like no other dynamic loudspeaker has -- in terms of ambition, design, execution and aesthetics. I would not hesitate to recommend them as worthy of serious consideration for anyone. And like any piece of equipment, I would encourage you to try to hear it in a situation surrounded by good ancillary components and showcased by dealers who appreciate the product and work to make it shine.