Made this with Clement rhum agricole, Pierre Ferrand Dry Curacao, and a moderately-spicy ginger ale. I agree with Paul in that I think ginger beer would be a bit much in this. The cucumber and basil are neither in your face nor too subtle. Base spirit on display, backed back some lovely complimentary flavors and measures. Good stuff.
I was afraid that cucumber will be first taste of this cocktail. But I was wrong. Cucumber cachaca and grand marnier are good trio for this concerto. Used spicy ginger but I think ginger ale would be better.