Typically most guys want dogs that have nice tight feet and up on their toes. But look at a lot of pictures, lots of dogs are doing well that are kind of flat footed. I have a friend who had a pure liquor bred dog that we laughed at as a pup because of his flat feet but man was that dog tough and he could go. Made fools out of a lot of us.
It is definitely a trait that is passed down but don't discount a pup just based on it.