I am not a gin drinker, so I'll defer to you there. Vodka doesn't have any taste to me with the amount-to-mixer ratio I usually use. (Haaaaate vodka anyway, it doesn't like me, so I avoid it if I can.) With rum, there are definitely flavors, so it's worth paying attention if the concentration is going to be higher in your beverage.

And congrats on your icon of the only beer I can stand. (That I can remember.)