The gimmick has no flaps and doesn't require to be attached to any bill. It is easy to carry
arround and easy to being in and out of play.
The gimmick's color discrepancy with real
bills is only noticeable if you put it side-by-side with a real bill. This routine doesn't do that
so you're safe.
Erik's and Gregory each teach multiple handlings, but the core effect is a
transposition. I made my own modification for the gimmick to allow four different bills, but it
isn't necessary.