Definitely! Any clear alcohol takes the color pretty well. The flowers have a taste though, so a well balanced, tasty gin might get that "unwanted" botanical flavour. Also (maybe obviously) don't cook the gin. The boiling point of alcohol is low, so by heating it up you will water it down.
They call it "Colour change", but it looks like it just makes everything purple and keeps it powerful. Can somebody clarify what colour the purple is supposed to change into?