I saw it at about age 10, but don't remember much (I got it and JFK's grave mixed up in my memory, I could have sworn there was a guard at JFK's...) Then I went to Difficult Child for 2 weeks in March 2006, and took myself out to Arlington.
I got there just before a change. I could feel my eyes tear up and then I was (quietly) bawling... I couldn't leave, I was rapt. I stayed for a second one.