Actually I do have factory NAV that is projected over the Speedometer. When a call comes in, the radio is interrupted, the radio screen says "incoming call" and the voice says "incoming call, press the u-connect button to connect ". After pressing the U-connect mirror button the call goes "live" through the factory speakers and the radio head simply says "phone".

 

Got this working in my SRT-4 after collecting info from multiple forums and crawling ebay for parts. Have a few extra parts if anyone is looking for them. Also got this working with my NON-Nav REV radio. At first I had trouble pairing but then I realized you just needed to walk through the voice prompt setup via the UConnect button for the phone to see it and sync over bluetooth.

 

You also have the option of something like this as well...

In Dash Radio Car DVD GPS Navigation for Jeep Grand Cherokee Chrysler Dodge RAM | eBay

I'm considering something similar for my 300m.

 

For me OEM or nothing. Also from experience these Chinese units are clunky and faulty. Fm reception sucked in the one I had and it had horrid input lag.