Q: When I run a profile, does it copy every file? Does it only copy new and changed files?
By default a SyncBack profile only copies new and changed files. This means when you run a profile for the first time, it will probably need to copy all the relevant the files from your source to the destination. However, on subsequent runs it will only copy files that have changed, and new files, so will be considerably faster. With SyncBackSE/Pro you can also enable the Fast Backup option for the profile to further decrease the backup time.