Depends upon why your family is considering boarding school.
For example: If seeking a highly competitive swimming team, then Mercersburg floats to the top, but for those who desire other things, then the focus may shift to other schools. Similar to those whose focus is on another sport, such as wrestling. If a highly talented and competitive wrestler, then Wyoming Seminary and Blair Academy become one’s focus.
If seeking connection to the best minds and highest ranked colleges and universities, then applicants typically look at a well known group of academically elite boarding schools.