• Simple and clean look
• Fast and responsive!
• Quick keys!
• Automatically saves mail sent to the “Sent messages” folder
• Automatically fills in To and Cc lines with Contacts as you’re typing their name
• Ability to highlight multiple messages for deleting or moving to sub-folder
• Preview pane
• Good sort-by options (date, from, subject & size)
• Easily move from one mail to the next without refreshing the whole screen

Cons:

• Not clear how to mark messages as Junk or Spam other. I can move them to the Junk e-mail folder, but I don’t know if that marks future messages from that sender as spam.
• Unable to adjust the number of messages or contacts listed on the screen at one time (10, 20, 30, etc.).  I would prefer to list 50 or 100 messages and scroll up and down rather then click the next arrow for every 14 messages.
• Lack of custom filters for routing messages to specific folders based on sender and subject line criteria
• No auto signature
• It was a little tricky determining how to view the full size email message the first time I used Kahuna. I accidentally double clicked the message title and that did it.