When the interface laggs it sounds like it needs a firmware update or its just faulty as i said, I’ve not seen such a problem as described myself.

Huh? The interface lagged? Wow, im doing remote “maintenance” on these for companies, I’ve never had such a problem, even with the smallest one.

The setup is a little work to get into, but Sophos does have a very good wiki for everything, the help button does actually help for them, and if not the support is always helpful even for seemingly small problems. They also have their own forum where you can get help for specific problems from the community

For the ipv6 to ipv4 problem, i doubt its capable of that, you probably need an extra system for that, i haven’t run into that issues myself but i seriously doubt it, even for the bigger ones and clusters.

I just have a small Sophos Firewall at home, it does the job very well, but its a little expensive compared to free versions.

I get it for free because i do business with them.