Support Multiple Forest not Trusted
STAS rocks! Anyway if you have to manage multiple Forests (not trusted) the XG cannot accomplish the task. Other vendors support this feature. This feature gives to XG a step further for use it in big environment.
When you will implement this feature, you should allow the Admins to decide if split the XG in multiple firewall (virtual firewall feature http://feature.astaro.com/forums/330219-sophos-xg-firewall/suggestions/11262702-virtual-firewall) or not.