I may be late, but have you considered Alpine head units? I have been using an Alpine iPod X100 "receiver" for a year now, and supposedly it also works with iPhone. You will control the iPhone from the head-unit to listen to music, and if you are happy with basic controls as skip, pause, on/off, you'll be happy. Audio quality is good as well. But, after 1 year, I decided that browsing my music collection is way to slow and inefficient. Nothing comparable to the empeg, of course, but also slower than the iPod wheel itself.
While your player is plugged into the head-unit, howevwe, I am afraid it will not be controllable from the player itself, which means that the navigator will be unaccessible.