i just got the cda-9807 intalled in my car and i have no qualms about it. it has great sound quality and the display is pretty good. I only encountered problems with the creation of the CD text, but i think they were problems because of the way I burned the songs into the CD. Regarding the MP3 functions, there is barely any delay, but as expected, the sound quality while playing mp3s with this radio is inferior to playing music cds.