1. Deployment Options: Catchpoint RUM can be deployed with JavaScript injection on the client-side, allowing for real user monitoring across different browsers and devices. On the other hand, Datadog relies on a JavaScript agent that is installed on the website's server-side, limiting its monitoring capabilities to server-side requests and excluding client-side monitoring.
2. Granularity of Metrics: Catchpoint RUM provides granular metrics and RUM data at the object level, enabling detailed analysis of individual resources loaded on a webpage. In contrast, Datadog provides more aggregated metrics at the page level, lacking the ability to dive deep into specific resources and their performance.
3. User Experience Monitoring: Catchpoint RUM offers extensive user experience monitoring capabilities, including the ability to measure performance from the end user's perspective by monitoring metrics such as DNS resolution time, connection time, time to first-byte, and page load time. Datadog, on the other hand, focuses more on server-side monitoring and lacks some of the user-centric metrics and monitoring capabilities.
4. Synthetic Testing Integration: Catchpoint RUM and synthetic monitoring tools can be integrated seamlessly, allowing for comprehensive monitoring and analysis of both real user data and synthetic test results. Datadog, however, does not offer direct integration between its RUM and synthetic testing capabilities, making it harder to correlate data and perform unified analysis.
5. Data Retention and Storage: Catchpoint RUM provides long-term data retention capabilities, allowing users to access and analyze historical data for extended periods. Datadog has limitations on data retention based on pricing tiers, potentially restricting the ability to perform in-depth historical analysis for long periods.
6. Alerting and Notification System: Catchpoint RUM offers a robust alerting and notification system that allows users to create custom rules and thresholds for proactive monitoring. Datadog also provides alerting capabilities, but it may not offer the same level of flexibility and customization as Catchpoint RUM's alerting system.

In summary, Catchpoint RUM offers more flexible deployment options, provides granular object-level metrics, focuses on user experience monitoring, integrates well with synthetic testing, offers longer data retention, and has a robust alerting system compared to Datadog.