I purchased a TomTom 510 to be used in a fire company vehicle. We have been running into a problem with unit turning on and off will driving down the road. After further research into problem, I found out that the GO510/910 had problems with the mount and were replacing mounts free of charge. I just want to thank the customer service reps that helped me resolve my problem and getting my TomTom back in service. That is the true meaning of customer service. Thanks Matt & Amanda