I stopped using (and recommending) APF quite some time ago. CSF does so much more and is so much more scalable. If you have any experience with programming, you can easily write a php script to manage firewalls on a global level using this. With APF/BFD/etc it's possible, but it takes a lot more work.
CSF is a breeze to work with, easily customized, no guessing at all. The only limitation (AFAIK) is that it requires CPanel/WHM which is bad.
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