First up, Quartz, which is one of the trio of polishes from Chanel for Fall 2011. It's a taupe-ish shimmer, leaning toward frosty-ness. I used three coats; I maybe could have stopped at two if I'd made them a bit thicker.
In most lights, Quartz leans toward being cool-toned, with silver showing in the shimmer.
In low light, it takes on a warmer tone, with the gold in the shimmer stepping up. Either way, it's a nice neutral, though I do wish the brushstrokes would settle better.
Maybelline Taupeward took four coats. It's also a frosty-leaning shimmer, and the light warm tan color blended surprisingly well into my skintone.
You can see from the swatches that Taupeward is lighter and warmer than Quartz. They do have a very similar finish, though.
Depending on your skintone and the look you're aiming for, Taupeward might be a better choice for you than Quartz. It's sure a heck of lot cheaper. Also, Taupeward might work as a layering polish, where Quartz is too opaque for me to even consider it.