I got the X910BT and it works FLAWLESS with the iphone..Supports everything but pandora(the newer x920BT does and apps like it)
The ipod player built it works great, shows album art and everythign, does playlist, videos, podcast, same exact thing as the iphone ipod player.
Bluetooth calls are the best i have ever heard with it, no lag at all and plays through all speakers in vehicle. Never heard a complaint of how i sounded, actually when i asked people they had no clue i was talking through the stereo instead of the phone.
Not sure what they go for now, but you could probably get one for around $300-$400 now since the X920BT came out this year. Amazon is high priced on here.
http://www.amazon.com/Pioneer-AVIC-X910BT-5-8-Inch-Navigation-Bluetooth/dp/B002EGVR6O