Justinwd - There are quite a few keys in the dime set, but it largely depends in the grade you are collecting. Just like the quarter and half set. The 95-O, as thecoinguy1964 said, will cost a bit in any grade. Most other dates below VG won't be too much of a hassle. There are a handful of dates in the G4 range that may cost around $40 or more depending on the condition of the coin.