ChemIT notes on specific situations where we have noticed Outlook outperforming Mail.

Microsoft Outlook provides a single application for email, calendar, and contacts.  Apple uses 3 different applications for the same functions, including Mail for email and iCal for calendar. The single MS Outlook application provide tighter integration, and some additional features, as well as better overall performance. Synchronization of Outlook across multiple devices has also proven more reliable. Apple's suite of products sometimes corrupts, and does not sync contacts or message folders correctly.

Specific situations ChemIT strongly recommends using Microsoft Outlook on the Mac

You have a large amount of email.

• Performance languishes in Apple Mail with just several thousand email messages.
  • Behaviors: Slow, unresponsive, unreliable/ gets confused

These problems are more common for users with large amounts of mail, especially a large IN box.

You have administrator responsibilities

• Outlook's calendar integration is often beneficial.
• Features for accessing group calendars, and managing rooms are not available in Apple iCal

You use a Cornell "special mailbox"

• Outlook handles it better than Mail does.