Spectrecoin (XSPEC) is definitely a solid pick.  (Not familiar enough with the others to speak for them.)

Spectrecoin is finally getting the attention it deserves!  This coin has some of the most robust privacy tech out there, several groundbreaking features, is super fast, and has a low supply of about 21 million coins.  Due to lack of marketing, the price had remained extremely low, but word is getting out and the price has begun to explode.  It is still well under $5 per coin, and I consider any price under $5 a bargain for this first rate privacy coin.

You can find out more about this hidden gem here: http://coinwiki.info/en/SpectreCoin
Join our vibrant and growing community on slack: http://slack.spectreproject.io/