I am new to these forums, but this question is one I am compelled to comment on. I have spent a lifetime busking in streets, bars, and, other venues.
After my tour in Viet Nam, I was offered a temporary position in Japan. I learned to busk in the streets, and railroad stations, and met many other street magicians. While performing in Tachikawa, I met an 80 year old man I came to know as O'sensi Yamaguchi, as my 3 month temporary duty became 6, O'sensi became my mentor.
O'sensi had grown up as a circus performer, and was quite famous before the war. War changes all, after the war he had nothing but his skill, and a family to support, so he took to busking. I introduced O'sensi to the book test, he liked the effect, but felt it fell short, and O'sensi never learned to read, the class system he was born into did not permit it.
A few weeks later this the "book test" O'sensi performed. 3 spectators are chosen, they are presented with 3 newspapers from today, the choose one, and one spectator is instructed to choose a page not the first, and to fold the paper repeatedly to a small size. O'sensi dresses in traditional garb with sword, assistant and 2 spectators mount watermelons on poles on either side of spectator holding folded newspaper in front of their face. O'sensi patters along time about the family sword, and its being the spirit of his family, very Japanese, when the crowd is nodding, O'sensi would split the 2 watermelons, with down strokes, and Pierce the newspaper with a stab. Then he would have the sword tell him what the sword saw, on the other side of the paper, much longer, and dramatic than described, later he even worked in a method of performing the effect with a blindfold on.
Which book test is the best?, the one you can perform and connect to your audience with, any effect can create a "wow moment", or "that's so cool", mentalism, is part Psychological, sociological, and cultural, the effect you perform should be a journey for both you and the spectators, you are no longer performing an effect, but just steering the roller coaster. The audience hoping you succeed in your attempt, as you are connected with them, and they with you on the ride.
A funny joke is "good" when you hear it, a funny joke is "great" when you are in on it.
Forgive my being a little long winded, and thank you for your perseverance.