It is cool, BUT it's not that practical...you just showed that there were multiple values of
cards....then they are all blank....guess what? The SPECTATORS now want to see the deck AND you
can't hand it out!! It's a cool effect, but this trick has sat in the drawer for more than 10 years
ago;when it was first put out!!! I'd highly recommend BLIZZARD or learn a deck a switch....sorry,
can't recommend it that much.
I do kids shows and I never let anyone handle any of my magic, gimmicked or not. I understand your concern, but I think you can use it, show it, square it and stick it in your pocket.