Yes, within the last week or so. We're no longer holding out; we're installing CSF on all our servers, with the maximum wrong logins set for ten. It's affected a few of our forgetful clients, but helped us overall.
After using APF&BFD forever (it seems), per your suggestion, we finally enabled CSF as well (it was installed but not active). The DA interface sure beats a Bash shell. The ability to utilize ISO country codes is pretty awesome, no more checking ARIN, RIPE, APNIC, etc.