BTCDARK – http://www.cryptobang.com/2014/09/24/btcdark-the-cake-is-not-a-lie/
A lot of good points in your review, one thing I had a problem with is you say the price is "unstable". Yes, the price rises and falls a little as with every coin, but the rise is a constant growth. Instead of looking at the day or even week long charts, take a look at the over all growth of the coin as exhibited by this cryptsy chart
Hi! I mean that price can be overrated. BTCDARK is the most powerful among any of anonymous coins for today. But it is hard to predict the future of all the anonymous coins as well.