Well I don't know about that but it is secure in the sense you won't lose it.
I know I couldn't care less if someone "stole" my music files but I honestly don't see anything to worry about myself.
edit: I did a search and it is safe as long as you don't screw up the permissions, like allowing other people to access it.
There is lots of info on it out there and there are very secure alternatives but most likely cost money.