Good quality, pretty colors--pleasantly surprised!
I bought one of the sets of 12. This is my second time using it (I've worn 5003 and 5001 so far--I wish these had names instead of numbers).  5001 is really very pretty--it shifts from a nude-y peach to a coral when it's cooler. The color change is very fast and noticeable. Like some others mentioned, some of the polishes are thicker than others (my first bottle was fine, the second too thick, but a few drops of gel polish thinner takes care of all that). On average, it lasts me about 10 days before it starts to chip or peel, but my hands are always in water and I don't wear gloves so that is to be expected and very good for me (my regular polish won't last more than a couple of days without chipping, so gels are a real time-saver for me).  The bottles are tiny, and you need multiple coats to build up the color, but considering that $20 will generally only get you 1-3 bottles of gel nail polish at the store (depending on the store and whether it's on sale), getting 12 small bottles of chameleon gel nail polish at this price is a steal.
Rating: 5 stars