Alright, thanks for the feedback. Maybe i will give both options also a try. My opinion regrading custom regex / SPAM Filter efforts: mostely it won't make any sense, as it will introduce actually more false-postives than before / without any of such custom rulesets introduced by single hueman for special purposes on their own mailsite....... @killmasta93 using SPF turned on as Default on PMG installation, so you should use it. While other settings turned off as default - you can experiment with, just my thoughts on it.. And having too much on against SPAM, won't automatically help more....There will be false positive but mostly is because the senders did not properly configure their email servers.
It is optional to enable the feature.
You can always use mail filter to filter domains/regex/from/sender.
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