Lets not tarr all hour builder FI's with the same brush. Two very good friends of mine are airline pilots but also still teach at weekends on their FI tickets. Both are still using it as a means to build hours yet both are highly thought of by club members and their flying/teaching skills respected. Neither of them are a day over 30 and have been teaching for a couple of years. I would happily fly with them any day of the week, probably more so than some hoary old instructor who who's got all the bad habits under the sun.