I must admit, I don't really use highlighters that often. I own a few, Dior amber diamond, one from my Fresh memoirs of a geisha palette, but they are just so darn pretty. I was lucky enough to swap for the Armani fluid sheer in #3. I wouldn't really consider it a highlighter on my skin tone, more of a bronzer or a bronze blush/shadow. I use it on my cheeks under blush or on my eyes built up for a sheer wash that makes my blue eyes really stand out.
The bottle has a pump applicator which is nice and sanitary but can be kind of a pain as it usually dispenses more than you really need. A little of this stuff goes a long way. It is sheer and shimmery and an orangey bronze color. I certainly wouldn't grab 3 if you have cool toned skin.
Here is a dollop for you, which is about how much it pumps out.
sheered out you can see how orangey bronze it is. It makes my cheeks really glow and pairs well under a peachy blush. I will definitely be pulling this out more in the summer months. I have a sample size of this color that I keep at the boyfriends house and use quite a bit more than my full size (oops).
Overall, I would definitely look into the fluid sheer. They look gorgeous and last a pretty long time. I could see this working as a great highlighter for darker skin tones. If 3 isn't for you, there are plenty of other colors, both in a more highlighter type color and in other bronzer type colors.
