European independent security software testing organisation AV-Comparatives just reviewed ten paid or free Mac products and found they all detected 100% of the 50 most recent samples of Mac malware and made no false positive reports.
The free products were Avast Free Mac Security, AVG AntiVirus for Mac, Avira Free Antivirus for Mac and Sophos Anti-Virus for Mac.
The commercial products tested by AV-Comparatives were Bitdefender Antivirus for Mac, Eset Cyber Security Pro, Intego Mac Premium Bundle, Kaspersky Internet Security for Mac, and Webroot SecureAnywhere Internet Security Complete for Mac.
But malware isn't the only class of threats, and not all of the products provide protection against phishing and other malicious web sites, for example.
There are other quirks, including Intego's very low rate of Windows malware detection and the way the Webroot product can be deactivated by a non-admin user, so the full report makes interesting reading.