Business email on your own domain, with the mailbox, the sending reputation and the spam handling all in one place.
Your domain, verified once
SPF, DKIM and DMARC are set up from the same screen that adds the domain, and every other product reuses that proof.
Search that finds it
Full-text across every folder and attachment, not just the subject line.
No per-seat surprise
Mailboxes come with the organization rather than being counted separately.