For me, there are three or four sets. Number one is the $40 set of six from the Hilton Atlantic City. I have been stuck on four for three years. These are the last strikes I need to complete the entire Atlantic City $10-$20-$40 strikes. This hole in my collection is compounded by the fact that I was born and raised in the Garden State. In second place is the $20 Mark Twain series from the Admiral in St.Louis. (I have one.)Third is the mirror set of $20s from the Players and Star in Lake Charles, Louisiana. This is a really unique set, with a Viking Ship, Steamboat, Schooner and Riverboat. I am seven out of eight on this one. Finally, and the most painful to me, is the Fitzgeralds Tunica $200. I was there and there were two in the cage but because they had posted their notice of redemption, they wouldn't part with them. I called again two days later and they had sold them to someone else.
There are a number of prototypes out there. Archie referred to the Trump Marina $20s. That is a set of six, with only four known to be in collector hands. (three for Christie and Tony, one for me.) Pam Corry has the only known set of five hunting and fishing $10s from Sams Town Tunica. There are three prototype $40s from Harrahs New Orleans, known mintage ten, two and two. I have a single one $40 of five from the Grand Atlantic City, Lucy the Elephant. Norm Wu has the $10 GDC Rio Rita. Christie and Tony have a generic $10 Fitzgeralds Mr O'Lucky and a Babe Ruth $10 from the Caribbean. There are three CT Flamingo Laughlin $10s. Anyone know of any others I may have missed?