Voltage Stabilizer, Power Conditioner, or both

I know there's lots of discussion of this issue, but I haven't seen a clear answer to this.

Here's my incoming setup:
McIntosh MC207
McIntosh MX119
McIntosh MVP861

With Vandersteens in the front and center; Klipsch in the back.

The room is not treated. I live in New York City in a condo building with all new wiring.

Do I need the stabilizer to protect my electronics? Will either the stabilizer or the conditioner improve sonic quality?

I noticed some improvement with an MIT Z-strip conditioner/stabilizer and my McIntosh gear but REALLY noticed the difference with my BAT and Kora gear. I guess the Mcs have very good power supplies and regulation to start with so they don't respond too much to conditioning (nor do they respond to power cords much). But this will depend on how well the wiring was done and what other components you are using. Give it a try and see what you think! Arthur
After using Monster (which constricted the sound) and Powervar, I now use an APC h15 (the s15 battery-backup one was Stereophile recommeded). At this point, I can't say enough good things about it. It has significant surge protection, isolated outlet banks and voltage regulation.
I use a panamax 5300pm
I live in a NYC co-op and the voltage is all over the place especially in the Summer. I use an Exactpower EP 15A on a dedicated line and now everything is rock solid.