The only two devices designed for in-car use as far as I'm aware are the Dension one and the PhatBox.

The PhatBox uses the factory stereo's head unit's CD changer controlling abilites to drive it, so is not able to display track information in most, if not all, cases.

The Dension is a replacement head unit, and can display such information.

Neither one's software seems to even come close to the empeg's, but the Dension seems to come much closer, if due only to the fact that it has a real user interface.

That being said, there is something to be said for being able to just plug in the PhatBox and go, without having to rip apart your dash.

All said, I'd go with the Dension, I think, but I'm glad I don't have to make that decision.