The only time you should use NoSQL is when you have no other choice. For example, if your database is too big to fit on one server, or you need a massive number of writes per second. Otherwise SQL will give you better performance, much more security, and better data integrity.
And much, much, much easier querying (if you know SQL). For me, the biggest disadvantage of non-sql databases is the difficulty of doing even the simplest aggregates!
