Dp37,
There is a current posting regarding your question lower in the forum list. Most amp manufacturers will suggest plugging directly into the AC outlet. Call them directly for technical advice, rather than "conditioner" manufacturers praying on your concerns. Not to say that they couldn't be used for protection of sensitive or low current drawing electronics (preamps, digital players, etc.), but may conflict with recovery timing of amplifier's instantaneous large current swings.
As with all your questions pertaining to aftermarket product equipment/tweaks, ask yourself why and how they could make a substantial difference in audio playback. How much of this so-called "Audiophile" technology does the recording in dustry utilize within their studio equipment? Very few! Just like with anything else, if there's a way to make money off the unsuspecting, maketing strategy goals are to suggest doupt. Just look at all the TV advertisements for medicine, personal hygene products, and the list is endless. Just try to understand what/why they're marketing.