Pioneer has an "Auto-EQ Mic" model CD-MC20. Anyone know if this is any better the the clip on provided with the Z series?

The mic that comes with the radio is for bluetooth hands free cell phone. The auto-eq mic sold separately is to setup the equalizer in "auto-eq" mode. Basically the unit will put varying white noise levels to each speaker and auto adjust the levels. You need to plug an microphone to start auto-eq setup mode. I used a mic from my Onkyo home stereo's similar function. It worked fine.

And yes the auto-eq settings were much better than anything I could setup manually by ear!