Has anyone used these services for anti-spam razo2, pyzor and dcc ??
Spamhaus (free API key) and rspamd (free to start for basic services) are effective. Also, just tuning Postfix for anti-UCE will get you miles down the road.
Do you have a tutorial on this please?
Spamhaus DQS:
https://docs.spamhaus.com/datasets/docs/source/40-real-world-usage/MTAs/020-Postfix.html
Rspamd:
https://forum.centos-webpanel.com/how-to/(howto)-install-rspamd/
Postfix:
https://www.akadia.com/services/postfix_uce.html
https://www.linuxbabe.com/mail-server/block-email-spam-postfix