The Royal Bermuda Yacht Club is a bewitching concoction of island flavors. the secret is in the Falernum Syrup. You can make your own (see recipe at link immediately preceding) of you can try to find John Taylor's Velvet Falernum at a quality liquor store. Falernum syrup is quite tasty - you may find a number of other uses for it, especially during the winter holidays thanks to its generous flavors of ginger, clove, and nutmeg.
The Royal Bermuda Yacht Club is a great islands/tiki drink when you want something a bit more sophisticated than a Hurricane.
I have had a Royal Bermuda Yacht Club Cocktail with dinner many times at the now-defunct Beehive Tavern on Rte 6a in Sandwich last week. It was always perfectly prepared. That's no surprise; the proprietor, Steven, used to work at the Royal Bermuda Yacht Club!