I just got this program. I made an image of the main drive...it took 18 minutes. Later that day I went to make a differential, and it indicates 35 minutes to complete. Is this the worst coded backup program ever, in that it apparently reads each file one by one? Doesn't this program have an indexing/catalog system? Or does it need to recreate on the fly by reading both the backup and disk? My other program completes a differential backup in 6 minutes max, or 1/3 the time of the original.