There are around 7 500 sorts of apples. No matter which one you use, it's a very nice garnish - whenever there's an apple ingredient in your drink. Try cutting the apple crosswise and make a cut from the core and out: It will look very stylish on the rim of a cocktail glass.
There are more than 7,500 known cultivars of apples.
Apples make an excellent and fresh garnish, but remember to remove the seed if the garnish is used in the drinks.
I've made Appletini's using Granny Smith apples, and I liked the two different shades of green. Don't make a big deal out of the color so much. There are so many different varieties of apples. Just make sure if your into the garnish thing that what you use is always fresh and not pithy, dry, or damaged. If you leave the apple out in between drinks remember to squeeze lemon juice on the cut apple so it helps to keep from discoloring so fast. Sometimes the prettiest isn't always the tastiest. I think if the garnish doesn't taste right your guest will forgo the little treat the next time around, and what a waste. I love the taste of the fruit when it sits and soaks temporarily in my glass. I figure you can never go wrong with a Granny or Fuji.