Originally Posted by WillysJeepMan
If your are referring to the Dropbox folder that resides locally on your notebook/PC, then be careful. If files disappeared from the cloud copy of your DropBox folder, those changes would be replicated the moment your PC connects to DropBox in the cloud.
Yup, thanks. I only ever make changes using Calibre on my desktop. I treat the folders as read-only elsewhere, but they are a convenient way to get at the books.
I have everything backed up locally as well.