Rated 4 out of 5 stars

There are eight 4 digit external DNS servers under the DNS Preferences. You use the OpenNIC servers so does one add those to the list?
I travel frequently, usually to China where I use a VPN; do I update the OpenNIC servers when I am in China?
I think more details of the preferences are required for amateur users such as myself.

This review is for a previous version of the add-on (3.0.8.1-signed.1-signed). 

You have the opportunity to change the list according to your wishes such as delete or add new servers. The list is not limited with 4 servers, you can fill it with so many servers you wish