I like that it has an easy interface, can be used by multiple people in different locations at once (using VPN), its cheap compared with other solutions out there - but also powerful enough when you want more features than basic email management! It's not as intuitive or user friendly if your team isn't familiar yet; however this will improve over time so don’t worry too much about learning how everything works right away. We use egroupwares calendar feature heavily because of our remote working environment which allows us all work together without being physically present each day/week etc., we have been able save hours per week just managing emails through egroupwise instead of having separate tools such as gmail calendars set up individually across several employees who are using them independently.