I must admit that I was a bit nervous at first when I didn't initially distinguish the difference
between the red & black cards... but after a minute or two I quickly picked up on the small
difference and within 5 minutes I was mixing the cards & could tell the difference between the
colors with 100% accuracy. If it takes a minute to catch this (after being told the secret)... I
can't imagine anyone else would ever pick up on this unless you told them. This (deck) and
principle can be used for so many other effects besides OOTW... I'm very happy with this purchase!
:)