Got a Kenwood DNX 5220 BT in ours, very pleased with it, it's the outgoing model, so if you shop around, should be within your budget, fitted myself, if you currently have a double din unit, it should largly be just plug and play.
http://www.kenwood-electronics.co.uk/produ...edia/DNX5220BT/
Garmin European Sat Nav
IPod control, lead extra £30
DVD / CD player
Hands free phone
Bluetooth music streaming from phone
Reverse camera, TV tuner optional (not fitted in ours)