Q: "One day old" — not recommended.

This article has in the picture "One day old" set, under Junk box emptying.

This is NOT recommended.

Example: fairly often legitimate irregular (non-junk) emails get filtered into the Junk mailbox wrongly. With this 'one day' setting, the Junk mailbox empty's itself after just one day.

This means that if you don't check DAILY that any legitimate messages are ending-up in there by accident; any that do will be deleted the following day, maybe before you notice them in there.

This may not be an issue for a few, but for most I'd suggest it would be.

Now depending on your workflow for dealing with emails, you have to decide which of the other options you want to happen (week/month/quitting/never). But one thing to be aware of is that the iCloud servers automatically delete email messages that have been in your Junk & Trash folders after 30 days anyway.

So personallly, I just set both Junk & Trash to "Never" on all my devices (as I do for the other mailboxes like Sent too, actually), as even using "Never" as your setting, the server will still delete them from the server after the 30 days regardless of your setting here.

Unless you are getting tens of thousands of spams, they take next-to-no space from your iCloud storage allowance, and once a fortnight or so at your leisure, just check the contents of the mailbox, and manually empty it.

Quote's from iCloud docs online:

• under "Delete Junk Mail":

http://help.apple.com/icloud/index.html?localePath=English.lproj#mm6b1a2ced

"By default, messages in the Junk folder are deleted after 30 days."

• under "Change where deleted messages are stored Mail":

http://help.apple.com/icloud/index.html?localePath=English.lproj#mm6b1a7ab7

"By default, deleted messages are stored in the Trash for 30 days."

(as an aside: you do have the option to make deleted messages be moved to a folder you create youself, if you do not want deleted messages to be deleted perminently from the server. Eg. create a folder named "Bin" and having them delete into there, then stops them being auto-deleted after a 30 day period.)

Hope this helps people decide on their settings.