The Mac version of Panda Dome Essential costs as much as its more powerful Windows equivalent but offers nothing more than antivirus and a limited VPN.
The premium edition of Malwarebytes for Mac scans for active malware and uses real-time detection to prevent infestation. It has a very good reputation, though hard data showing its effectiveness is scarce.
Intego's combination of malware detection and eradication plus active network monitoring and reporting makes it an effective solution for the latest threats.