Cap_n Pickard,
If you live in rural areas subject to frequent power outages and/or voltage spikes, there is some utility to power conditioners, however none of these devices will protect against a direct lightning hit on a transformer or phone line outside your house.
In urban areas, there is no need whatsoever to "condition" the power source. That is what the power supply and filters in each of your components in fact does. Claims made of improved sound quality and the like are fraudulent and are not supported by scientific tests. I lump many of the manufactueres of such devices right next to the exotic cable sellers in terms of ignorance of the laws of physics and electrical theory, as well as the absurd claims made for improved audio performance. Along with expensive cables, power conditioners are, of course, a huge source of profit for retailers.
Ground loops are solvable through the device you mention, and other similar inexpensive ground-lift devices or in-line cable-TV transformers.
Regards,
