I’ve been using this for years. It’s like a secret weapon. The Frixion Control is always in my deck.
Spectator selects a card. Card is replaced. Spectator can overhand shuffle for days and with just
one shuffle, you find the card. Several other great tricks are possible. Is it expensive? Yes. Do
you absolutely need this? No. But if you want to kick up your card work and make some of your
existing effects/vanishes better, this stuff is great.