I first purchased and installed a Pioneer Avic unit. It was so bad I got the company to take it out and install the Kenwood 9280bt. And what a brilliant unit it is. It has a reverse tilt screen that can be removed for security. The screen is also much brighter and clearer. The Bluetooth works perfectly with my iPhone 4. You just pair the 2 and either use the hands-free or audio functions
Kenwood DNX-9260BT 5.1 Surround Sound Multimedia Unit You can also connect a USB stick, iPod/iPhone, insert CD for further music playback, plus play a DVD movie.
The 9280 has voice commands too and I have found this to work very well. You just press the dedicated exterior button a speak View Map, Bluetooth Audio, iPod, CD, Tuner to name but a few speech commands and it switches to them.
I also had the rear camera installed and this is just amazing. You touch the screen on the right and it will scroll through normal, zoom, overhead, combination split screens views etc. Tap on the left and you have a useful reversing guide.
Yes this unit was almost double the cost of the Pioneer, but with the inferior mapping, tiny on screen buttons (Way too hard to use while driving), plus the voice commands, better screen. It was money well spent.
I purchased and had mine installed by CarAudioSecurity who sell on Amazon. Very professional installation.