Gold vs Silver vs White...

[Snoopy8]

The reason I’m asking is that as much I can understand how they can be beneficial for a traditional speaker which does not have mechanical cancellation of forces generated by its bass driver, the phantoms do not generate any vibrations, thanks to the two woofers working in opposition. 

So what would be the use of the elaborated vibration absorption then?

Even with opposing woofers, there is still small vibrations in the Phantoms that can cause smearing of instruments.  It is not obvious until the Isoaccoustic stands are used.  I was using them for my home theatre speakers and decided to test them on the Phantoms.  Adding the stands reduced smearing and improved the clarity, with a small improvement in the sound stage.  Ended using the silver coloured Aperta 100 rather than the black coloured Iso range because black colour was clashing too much.  Could not tell a difference in sound even though Aperta was more expensive and was supposed to be an improvement over the Iso range used in professional audio.

Another advantage is they allow the Phantoms to be tilted to ear level, especially if on a low table.  I recommend a flat board between the Phantom and stand, otherwise the Phantom sits awkwardly and the 2 Phantoms are not at same angle.

Obviously, it cannot be used with Devialet stands but I believe the sound improvement is sufficient to convince some people to skip those.

This is a relative cheap tweak.  Even cheaper if black Iso is acceptable for Premier range, and ideal for the black Reactors.