I love in the UK too, but I don’t need £20 to do it.
The article says there are 150 million Elgar notes in circulation, more than enough to give every man, woman and child in Britain two each. I doubt it could be considered a ‘collectors’ item in our time except in uncirculated condition. You’d do better to buy a silver Britannia or Maple Leaf coin with that £20 that will hold its value against inflation more than a note that will only ever be worth £20, no matter how much £20 is worth in a time of continual inflation...