How important do you think the transfer of large attachments is?

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iCloud storage, backups and pricing

Beyond simple data syncing, iCloud is used for storage, similar to DropBox or Microsoft's OneDrive. You can upload, share and store documents and data and then access the docs and data from any computer with a web browser. iCloud is also used to store and transfer large attachments sent from Apple's iCloud email addresses.

How important do you think the transfer of large attachments is?