I recently painted my nails with Glitterati from an Illamasqua nail polish duo. Glitterati is a deep violet/maroon color with flecks of variously sized duo-chrome glitters. The nail polish needs about two coats to reach full opacity, although I went for three coats on some nails. The finish isn't as shiny or glossy as one might expect, and it isn't completely smooth either, although adding a top coat usually fixes this problem. I like Seche Vite as a top coat for this nail polish, however mine has almost dried out and is pretty stringy. I used Sally Hansen's diamond strength in Flawless for all most of my nails instead.
With one coat, the nail polish is almost opaque, but you can see where the color is thinner.
The duo also comes with a deep teal called Viridian. It's a really pretty deep teal/jade color with a very shiny slightly metallic finish, although I find that this one chips a little quicker than some other nail polishes. Glitterati tends to last pretty long, although that might partially be the result of always using extra top coat with it.
This duo cost $25, although I believe this was a limited edition nail polish duo and is no longer available.