I just purchase another car, the car that i purchase has a ROSEN ds-mz1010 p11 stereo http://www.trailduty.com/docs/Rosen/Mazda3.pdf , on it it is capable for navigation but the sd car with maps is missing, i would like to know if someone has a way how to get these files to have my nav working on it or if its better to purchase another unit and what kind will be the best..... thanks for the help provided