AVIC N2 and XDV P90 DVD Changer

I recently purchased both of these items (AVIC N2 and the XDV P90 DVD Changer).  The N2 is scheduled to arrive next week for installation. 

I emailed Pioneer about using the Navigation discs in the DVD Changer, and they said it was not supported.  However, does anyone know if you can use the Navigation discs in the N2 DVD Slot and still play music/dvd's from the changer at the same time?

FYI in case you are interested.  I contacted Pioneer directly with this question as well.  They stated:

"While the navigation disc is in use in the AVIC-N2 slot, the DVD

So - this is a nice work around to having to take the Nav discs out of the drive and rely on the memory...