I've gotta agree with Charlie on this one. I love my rear center. I went through some hassle to install it, but IMO was well worth the effort.

For some other good demos, check out the rooftop bullet dodging sequence in The Matrix and pretty much the entire Episode One, but specifically the pod race.

I just leave mine on all the time. That way anything that comes on on the satellite with DD I also get in six channel surround. Even my wife likes it!