I went into the importance of impedance matching, and other stuff in my original post, but it didn't make it, clicked over to something else, and when I came back all of it was gone.
Most of the circuitry, of the items Hal and I posted are the same, except that the one Hal put up is in a box, and has selection switches. Which makes for a nice clean install... And since impedance matching is the idea here, using recommended volume controls also affects this. And a seperate amplifier is recomended, as a theater type 4.1, or 6.1 does some wierd things with adding reverb, and other effects to the channels, not appropriate for use in other rooms, outside of having limited power for each channel.
Using a 6 channel amp would aslo work, or if you had run some control wire to the VC locations, a multi-zone/multi-source system would be even better - Why spend less? A few dollars more and you can can control the whole works. But some planning early must be done, as it is a "System".
Another source for this type of equipment is Niles, and there is often debate over which is better quality..... http://www.nilesaudio.com/index.html