What you are asking is a very tricky question. It is more a matter of salesmen than dealerships, although some dealerships are more forgiving of a little stretching of the truth, if the salesman has good numbers. I've actually gone to a salesmanager and told him to keep a certain salesman away from me. He asked why and when I explained that the salesman had stretched a MHs fuel economy by 5mpg and wouldn't budge from his claim, he honored my request. Ended up buying two RVs from that dealership. Maybe they just realized that I do my homework and they couldn't BS me.