It's free and easy to use! So we do not have an extra cost for training or implementing email security at my organization (although I'm sure it is there). You can add additional features like S/MIME signing of emails if you want them now but this isn't necessary when using basic filtering options first. Make your employees more comfortable with security by giving users access to all aspects when they sign into their work accounts online without leaving home or office. I like how easy it is configure with my mail server (microsoft exchange). It's very accurate so you can trust only your emails are protected from spam or viruses without any mistake! Some features could be better implemented but i think they will improve their product soon because of its popularity among users out there who used this software before now. Easy install & configuration process even when using Exchange 2016/2013 servers - no problems at all!!