I asked about compatibility before purchasing, and they also asked me about specific features I needed to make sure I could use them properly, and it was clear they did not want to sell me something not compatible to my vehicles. After a few days I received a list of features I could use, and those that were not compatible with my vehicle. A few days later I received a list of features that I could use and those that were not compatible with my vehicles. The user interface is very user friendly and easy to use. The downside is that I would have liked the manual to be more detailed about all the features, which would have been more helpful for someone of my age.