I wouldn't do this unless you also purchase Premium Support and get a committment from Astaro that you will have hardware support. If you were my customer, I would sell you an HP server for this application instead of a 320. You also might want to get a new 220 on trial to see if that does all you need.
Cheers - Bob
Sophos UTM Community Moderator Sophos Certified Architect - UTM Sophos Certified Engineer - XG Gold Solution Partner since 2005
