I've used it mainly for Tarot and photo switches. As an example, I was doing a kids' show on New Year's Day with an Alice in Wonderland theme. I had the Cheshire Deck with me, and swapped out the Magician card (Cheshire Cat) for the version with the cat disappearing, then back again. The wallet handles brilliantly and makes any effect involving the switch of a card or photo much, much easier.
In fact, I'm so pleased with it that I'm reworking some effects with different handling (such as Dave Forrest's 'Freak') specifically to use the wallet.