When you select ‘Delete Duplicate Photos’ option, you instruct PicBackMan to delete all duplicate photos from your account permanently. The change is irreversible and there is no undo. However, you can click pause button anytime during the de-dupe process.
PicBackMan is a free photo/video uploader that helps you to keep your memories backed up to your favorite online services.
Users in 130+ countries have backed up.
... an excellent job of uploading more then 300GB of photos to 2 different services