One new great improvment for OA Firewall Free
it's that now the users can enable
"Run safer unknow programs by default" ...This option was restricted for OA Firewall Free in the previous versions and available only for the paid versions.
Go here and read all about "Run Safer" > http://www.tallemu.com/webhelp3/KF-RunSafer.html
For thoose who are usign OA Free,don't forget to check this option.
Also OA added to their Free Firewall a "Web Shield"
What dose the "Web Shield"? > http://www.tallemu.com/webhelp3/KF-Web.html
As for the resource usage....It's very light(20MB of RAM),i've tested it in my VM and didn't felt any slowdown what-so-ever.