1. Cost: CommentBox.io is a paid commenting platform with various pricing plans based on the number of comments and features. On the other hand, Commento and Talk offer free open-source solutions with the ability to self-host, allowing users to have full control over their data and customization options.

2. Integration: CommentBox.io is designed to be easily integrated with websites through code snippets, making it suitable for non-technical users. Commento and Talk, being self-hosted solutions, require more technical expertise for integration, but offer greater flexibility and control over the commenting system.

3. Privacy: CommentBox.io collects user data for analytics and advertising purposes, which may raise privacy concerns for some users. In contrast, Commento and Talk prioritize user privacy by not collecting any personal data unless specified by the user, ensuring a more secure commenting environment.

4. Customization: CommentBox.io offers limited customization options in terms of appearance and functionality, with users being restricted to preset themes and features. On the other hand, Commento and Talk provide extensive customization options, allowing users to tailor the commenting system to match their website design and requirements.

5. Moderation Tools: CommentBox.io provides basic moderation tools such as comment approval and filtering, but lacks advanced features like comment threading and user banning. Commento and Talk offer more comprehensive moderation tools, including thread management, user blocking, and real-time updates, enhancing the control and management of comments.

6. Community Support: CommentBox.io offers dedicated customer support through email and live chat for paid users, ensuring timely assistance and troubleshooting. Commento and Talk rely on community-driven support through forums and online documentation, providing a collaborative environment for users to seek help and share insights.

In Summary, CommentBox.io is a paid platform with limited customization and moderation tools, while Commento and Talk are free, self-hosted solutions prioritizing user privacy and control.