Kenwood DDX7701HD
I got mine refurbed, so it was quite a bit cheaper than that.
Mine does mirror my phone - I can open any app and the video appears on screen, and the audio comes through the speakers. Both the phone and the unit are fully operable, although the unit doesn't support multi-touch. I don't even see the Kenwood app unless I want to re-calibrate the screen. I will say that one thing that bothers me is that the phone's screen must remain on through all of this.
I don't know when the first time you tried it was, but technology is a vastly expanding field. If you fall asleep for a moment, you're going to miss a lot. Then again, I do have a $600 unit, a lot of the ones we're talking about retail for half of that, so it could very well be the case that the features I experience haven't trickled down to the less expensive models yet.
I'm not advocating one way or another, I'm just trying to insure everyone who's looking is as well informed as possible. Again, I don't mind taking a video showing it in action, or even just taking some pictures so people can see it installed. No sweat off my back.