About 3 months ago, I installed a Kenwood DNX570HD to replace the factory unit. It's a great upgrade with NAV and Bluetooth. I also installed the module that allows you to keep the steering wheel controls, and connected it to the factory sub-woofer. I did not connect a back-up camera, but it has this option.
This unit has been updated (571, I think) which improves the tiny clock in the top-right of the screen, and it looks like they've changed up the overall interface a bit. The dim settings are also difficult to impossible to find...touch and hold the bottom-left corner of the screen for options.
I really like the improvement this unit made. It's like having a brand new truck with all the bells & whistles.