if you have the 10 speaker system, you really do NOT need to upgrade the speakers... just swap out the amp.
anyone coming to the national is more than welcome to hear my system, on which I just replaced the amplifier.
Guarantee you wont get a better sounding system without spending mega money on it.
Yes, Carver/DSP is the best OEM solution, but the difference between the DSP amp and a decent, well set up aftermarket amp is astonishing.
I'm not ever running the rear mid speakers any more, as there's very little point.