While we can't speak to the day-visit, our family highly endorses the overnight-visit experience for anyone who is able to make the trip. Being exposed to the cadets was so special and informative to our boy. He learned so much about what would be expected of him. As parents we search for info and insight online and as we come across a tidbit that is new to us, we share it with him. About 98% of the time he tells us, "Oh yeah, they told me that when I was there." The bottom line result was that he is extremely comfortable with his choice; and even though he knows there will be challenges, he feels it is do-able for him and looks forward to being a cadet. All the credit goes to those cadets (and officers/instructors) that took their time from their other obligations to be so open to him.
By the way, we have found West Point to be very "parent friendly."