Thanks! I will check it out.I like the Garmin Mat Pilot. It is very much like a Garmin GPS that you would buy. On interstate roads, the screen splits as you approach an exit. One half is the map, and the other half is a picture of the exit with arrows showing which lane to be in, no guessing. The SD card can be bought online from eBay or Amazon for less than $100 compared to the dealer at $600. You can update the firmware and maps free using Mercedes Download Manager. It does not tie up the phone if used for other things.