I just installed the JVC KD NX-5000. it is pretty awsome.
Sonicelectronics have refurbed ones cheap, ask for Darin.
40 Gig Hard Drive and it is Ipod Ready and plays MP3 Disc's. GPS and DVD too.
Hell if your ipod has Bluetooth, the unit connects to that too. You need a Bluetooth Adapter JVC.
Just installed a Plug & Play JVC Compact Amplified Subwoofer under the passanger seat. My baby goes BOOM :-)
Installing Back Up Camera too.