Originally Posted by Dr Millmoss
I wonder whether never deleting won't become a problem on my mail server after not very long, and also whether setting up the POP side of the account this way won't cause longer IMAP syncs.
It depends on how many emails you get and your server account limits. Plus, deleting emails from your IMAP account will delete them from the server. You can also set the POP account to remove emails after a certain time. So say you monitor emails using the iPad, your desktop is sitting in another room downloading email too, once the emails are downloaded, the desktop can delete the server version 1 month after downloading them. This way you get 1 month to see them in the IMAP account.
Another option could be to use POP on both iPad and desktop because itunes allow you to sync mail accounts up and again you can simply set the accounts to delete email from the server after a certain amount of time. This way you can search archived mail on the iPad. I'm not sure if this syncs back email deletions though.