"Charcoal" is a dark metallic grey with tiny specks of silver. I think because this was a metallic gel liner, the formula was comparatively dry because the gel/cream is packed with tiny metallic particles. So as a result, it doesn't go on superbly and it isn't as opaque as expected. Also, the product seemed to have shrunken quite a bit since I bought it seven months ago. All in all, it's not horrible and still useable after seven months.
As the name suggests, "Brown" is a simple dark warm brown creme with no metallic elements. It is pigmented, very creamy, and very easy to apply. After owning this for more than seven months, it is still good as new, I did not notice significant drying of the product.
The wear of these are fine, they don't fade or smudge as along as you don't tamper your eye area with your hands. Also, a makeup remover is preferable when taking these off. I use my Shu Uemura Cleansing oil on my eye area, and the gel liner, along with the rest of my eye makeup comes over completely.
Over, I do recommend these, and especially because they are so affordable, they are worth a try!
Hope that review was helpful, thanks for dropping by!