I bought Twisted Sisters like 5 years ago when I first got into magic, and it instantly became one of my favorite tricks. However, I didn't really perform it much because it was gaffed and I don't like carrying around stuff with me especially if it can't be examined. So Twisted Sisters went into the magic junk drawer.
(fast forward 4 years)
John Bannon has done what magicians were waiting years for - create a version of Twisted Sisters that is examinable.

Enter Duplicity...

Effect: Same exact as Twisted Sis. but with aces.
Slights: Only one slight is used, and it's a slight that every magician knows (and if they don't - John teaches it in depth).
Difficulty: The hardest part is remembering the patter. You are gonna have to remember some patter, but it's quite simple to remember.
Practicality: EXTREMELY practical. You can so this trick for close-up, walkaround, and stage (if you have a projector bec. the cards are small - but you can always use jumbo cards).
Set UP/Reset : 3 seconds each.
Reactions: Worth a LOT more than .25
DVD: Very well made. And you get an AWESOME bonus effect which kills people!

Conclusion: If you don't have Duplicity, buy it. NOW. You won't regret it.

I reckon this is worth the 11.25. It is a one routine item, but there are some helpful, subtle insights into the way JB presents "guiding" the spectator so that it all looks like free choices. (Unlike Twisted Sisters, this set of cards isn't gaffed and can be examined). Also, he gives some helpful insights into the basic sleight and explains why different handlings fit different situations.

I was amazed by the video and when I got the package and saw how it was done I was almost disappointed by its sheer simplicity, but then became even more awestruck by its total deviousness. By the way the bonus trick that comes on the CD is quite strong as well--I was expecting something a bit more "throwaway" but it is a quality trick and both will leave your audiences scratching their heads.

Simply a great effect that is easy to learn and will astonish people of all ages on the street or on the stage

This is a elegant magicians effect...it has class. Its simple, short, sweet...brilliant. Cards are examinable. Enough said. Add this one to your collection.

John Bannon have never failed us, this trick is so simple yet so strong. Very easy to perform, no sleights of hand is needed, end clean and everything is examinable(this is what beat twisted sister). The price is way too low for this gem in my opinion.