I have three vehicles each with Nav from three different manufacturers. The 2010 X5d nav is the easiest to enter and easiest to use of the three (others are Acura and Toyota). I also have two moveable/portable Garmin devices. However, the accuracy of the maps and directions in the 2010 x5d is the worst of the five units, by a long shot. It regularly tells me to turn right when it should say left (big problem). The most common one is for a slight curve in a road to call for "a right turn followed by a sharp left turn". Frustrating. I fear some idiot will drive off of a blind cliff following the wrong directions on this thing. Somehow we need to send BMW and TeleAtlas a strong message.