Actually in my experience, there are many FI's who want to act like FE's on checkouts. Especially required checkouts. Many of them are hour building boeing-gear-operator-wannabes who are just doing it to fill their time until that can get their hand on that gear lever - later on they get to operate the flaps too I am told...
But on the other end of the scale, there are some brilliant ones who's advice is worth every penny. They tend to be the career instructors or those that instruct not because they *have* to but because they enjoy it.....