Hi, i wanted to share my Experience with a Sophos SG330 Rev1. and Opnsense since other Posts, Knowledge on the Internet is a littlebit older.
Opnsense on an SG330 Works. well who tought elsewise.
Problems i occourd:
Installation: I had to remove the Drive and install Opnsense using a diffrent device. After that it booted opnsense.
Console Port doesn't work per default after the installation, you need to change it in the settings of Opnsense.
Interface Mappings: IGB(InterfaceNumber visible on the Device). So if you don't know which interface is what, check on the Device and you have the . . numbers.
LCD: you need the Plugin to get it working otherwise it shows "ALWAYS" Sophos Protection.
Interfaces: Im still trying to get the SFP+ Interfaces working. The Trancievers are working (Ooh a red light is shining in them) but i cant get the interface online so i might send an update for that in the Future.
Overall: I think this is a nice & cheap opertunity for some Homelabs to get a decent Firewall Appliance.