Note that tms13 has problems with one of these adaptors; it just didn't work with the tuner module. Not quite sure why, the design internally looked sensible enough. It did do some funny things - eg, "overload" the buttons to get more functions out of them, which may have been fine on a sony head unit, but just confused things with the empeg in place.
If you do get one, remember to hook up the power wire and also to get an assurance from the supplier that you can return it if it doesn't work with the empeg.
Hugo