It would be somewhat surprising if the caps made a large sonic difference in any system. It would imply that you live in a horrendous RF polluted environment. I use the product and I cannot honestly say I heard a positive sonic difference. At the same time I can say that the Cardas caps did not screw up the sound of my system -- which is more than I can say about some other tweaks I've recently tried. At a little over $2 a cap, if the only thing they do is keep the unused connectors free of dust, I think they're a reasonable value.
