I like Sophos Virtualization Security in particular the virtual appliances built-in antivirus and firewall security and threat protection equivalent to the hardware appliances. These virtual firewalls are pretty stable. With valid subscription You can easily deploy a web application firewall, secure email or web gateway, VPN, next-gen firewall or unified threat management system within your existing virtual infrastructure.

The most valuable features of the solution are VM security, VLP, and threat protection.

The SVM deployment has very good performance.

The most valuable feature is MAC-based security settings available with the VPN. We are in an academic environment, and teachers want some internet access blocked, whereas the students want access to it. Using this solution allows us to set up rule-based access control.

When it comes to their firewall, it notified me about a possible infection.