I know there's already a review, but this is written by ME

The Effect
"You get the attention of two spectators, inviting them to participate. You place two small packets of cards, one red-backed and one blue-backed, on the table. Your give your first spectator the choice of either the red or blue packet. You ask her to imagine that the packet consists of the four Queens and to merely think of any one of the Queens. (There is no equivoque: your spectator may choose either packet and any of the four Queens.) Now directing attention to the other packet, you ask your second spectator to think of one of the remaining Queens.
You boldly state that you will cause the two thought-of cards to change places. After a magical gesture, you invite your two spectators to reveal their thought-of Queens. You spread the packets fairly on the table and the thought-of Queens are now face up. The Queen in the blue packet, moreover, is red-backed. Similarly, the Queen in the red packet is blue-backed. The thought-of cards have indeed “changed places” with each other.
You lean forward and hazard a guess that one question is on everyone’s mind: What would have happened if either spectator, or both, had thought of a different Queen? You remark with a relieved tone that it’s a good thing they didn’t, because the trick would not have worked: You turn the remaining cards in each packet face up revealing to an astonished crowd that they are all Jokers—not Queens at all. "
As quoted from Penguin. The effect is exactly as performed here. No (I repeat, NO) sleights are required, although an E*****y count makes it perfect.
Cost
$11.95 from Penguin.
Difficulty
(1 = self-working, 2 = No sleights, but not quite so easy, 3 = Some sleights used, 4 = Advanced sleights used, 5 = Suitable for experienced magicians only)
It can be anywhere from a 1 to a 3, depending on the presentation and the preferences of the performer.
Review
Trust me, this trick hits them HARD. I learnt the required move within a week and was soon frying spectators with ease.
There's only one problem: although the 'reset' just consists of putting the cards back the way they started, you can't let the spectators see this as they will immediately get a major part of the trick.
I also don't recommend repeating this trick, as the more able-minded spectators can sometimes deduce how this is done.
Apart from that, this is a killer. ADD TO CART now!
Overall
9.5 / 10 - the 'reset' is troublesome, especially because this is one of those tricks with the 'do-it-again' factor. Apart from that, I can't find anything to fault it.