For me, Android SMS Backup is definitely convenience over security.
However, some type of SMS backup is required: if the Android SMS SQLite db is ever even slightly corrupted (power loss/program crash [usually when db is large]/etc.), Android will silently delete it: http://code.google.com/p/android/issues/detail?id=10127
However, some type of SMS backup is required: if the Android SMS SQLite db is ever even slightly corrupted (power loss/program crash [usually when db is large]/etc.), Android will silently delete it: http://code.google.com/p/android/issues/detail?id=10127