Advantages 

POP:  

• Easier to use
• Less bandwidth intensive so recommended for dial-up users

IMAP:

• Almost all emails and folders remain in synch with our servers and across multiple email software installations, including your Junk-Mail folder.  This is great for the traveler, or person that works from home and office because virtually every email and every folder remains on the server and in your email softwaer profile, and remains in synch automatically.  So your webmail and your outlook will have the same email at your fingertips.
  
  
• Your mail will be stored on the server, and included in our backups, so you will not risk losing any mail should you have a hard drive failure
  

Disadvantages

POP:  

• You'll have to log into your webmail to view any spam that is waiting for you should you be missing a message you are expecting in your inbox.  From there you would mark messages as NOT JUNK to whitelist and deliver to your email software profile inbox.
   
• When you download an email, it usually gets pulled off the server so when you travel you won't see your same email folder structure and organization.

IMAP:

• Requires a few extra steps for day-to-day usage. 
  
  
• Deleting Messages: If you want to delete a message but keep it in your trash without getting rid of it forever, you'll want to drag the messages to your trash.  Rather than removing the deleted message from the inbox, the trashed messages will appear with a strike through as if scratched out, and you will have to chose to purge messages to completely remove it form your inbox. The new copy is then placed into the trash. 
  
  
• Folder viewing / subscription.   Depending on the email software, you will have to subscribe to folders to automatically view their contents, however an easy way around this is to tell the software program to show all folders, even those you are not subscribed to. Generally you would want to subscribe to your inbox and your Junk-mail folder.
  
  
• Sent Messages: Also, if you want your sent messages to appear online as well, you will want to remember to drag and drop the sent messages from your email software profile into the sent messages of your IMAP account.