Isolation devices are important aspects to get the most out of your gear... I would say it is at least as important as power conditioning, but is taken much less serioulsy, and in this thread you can still see the ridicule it takes.
Even in a headphone system the gains can be clearly heard with proper isolation. Of course external variables come into play depending what kind of floor, foundation, etc to overall sound.
Not all the vibration control devices have all positive effects on the sound as some of you have discovered with the vibrapods, which can also be true for cones as well.
Isolation devices for me have worked the best, and even then, as far as bearing isolation devices, they do impart a certain sonic signature to tonality depending the brand used.
The best I have used so far is a isolation platform made by K Works (of the Empowered power cord). This is really his main specialty is dealing with parasitic vibration.
Here is a custom made isolation base made for my DI/O based on his regular isoaltion platform. The effects of the isolation is quite substantial, where without it, the presentation is that as if it were in a box, with the isolation device the headstage is quite a bit more expanded where you get a real sense of space of the recording, along with other benefits.