The ease of use, and how simple it is to create and customize your own templates. I have used several other programs in the past, but this one is by far the easiest to learn and use. It has helped our business tremendously. We are able to produce professional looking marketing materials for our customers at a fraction of the cost compared to our previous printer. There really isn't anything that I dislike about this program. If you are considering using ZetaPrints, do it! You won't regret it. ZetaPrints has allowed us to produce high quality marketing materials at a much lower cost than we were previously spending.