You have to bear in mind that when you are in the process of purchasing a new vehicle you have been researching the bejesus out of one or two cars, the sales staff usually have to know a bit about all vehicles so it is any wonder that we do know more than them. This is nothing new, I used to use a Holden Fleet Salesman that had no problem telling me not to ask him any questions about the cars as I would know more than him. You have to remember that they are usually not passionate about cars, they just sell them. I know that I'm not passionate about my work but I'm passionate about pay day.