Both Guardio (free) and Malwarebytes Browser Guard offer strong malware protection for your browser. Guardio is known for its advanced threat detection capabilities and comprehensive online protection, including antivirus, phishing protection, and secure browsing features. Malwarebytes Browser Guard is popular for its powerful ad-blocking, anti-phishing, and malicious website blocking features. Ultimately, the best extension for you will depend on your specific needs and preferences.