How safe is the user's privacy on your network?

Very safe. The connection between you and our equipment is secured with industry-standard encryption and cannot be easily tapped in to in the same way that a copper connection can be, because the signal is not electrical, it's light.
It is, however, up to you to install appropriate security software (anti-virus and firewall) on your computer(s) to ensure that you do not become infected with malicious software (malware).