The £100 note is scarce in UNC [68 or higher] as the notes did not generally circulate and were always difficult to obtain from banks, and very difficult to obtain in UNC.
Even from when it was first issued, the £100 note carried a small premium in UNC.
Circulated examples of the £100 note are also somewhat uncommon, and fetch surprisingly high prices - well above double face in VF! Issue quantity of the £100 note was between 2,000,000 and 3,000,000 notes, far below its likely printage of 6,000,000.
Though the the 2001 £50 note is scarcer than the 1999, it is not a particularly rare note in UNC. However, it should be noted that it is over 20 years since the notes were issued, and supply has been well drained. Very few notes that were kept in quantity by dealers now remain in those initial stocks, so any notes turning up will have been in collections and are appearing on secondary markets. Any examples that do turn up from non-numismatic sources are seldom in UNC grade.
