I recently exported several old email accounts into MBOX format from a legacy email client. Now I am planning to convert these MBOX files into another format for better accessibility and long-term storage. My main concerns are data integrity, metadata preservation (like To, From, Subject, Date), folder structure, and compatibility with modern email clients. Some colleagues suggested converting to PST for Outlook use, while others recommended EML or PDF for archiving purposes. I am a bit confused about which format would be the most reliable, depending on different needs such as backup, migration, or legal compliance. In your experience, which format is generally recommended after MBOX conversion, and in what situations would you choose PST, EML, MSG, or PDF?