Slice the kiwis in half crosswise. Scoop the flesh from each half into a blender.
Add the mint leaves, lime juice, rum, and honey or agave. Blend until well combined. (There will still be visible kiwi seeds, and that’s okay!) Taste, and feel free to add a little more honey or agave if necessary.
Divide the kiwi mixture amongst four glasses filled with ice. Top each cocktail with club soda. (I recommend 2-3 ounces per cocktail.) Garnish with a kiwi or lime round if you like.