I like being able to communicate through an online platform rather than having my designs printed at home or sending them via email! Sometimes it's not intuitive how things will look before they are completed; however their customer service is top notch so we can always contact someone if there isn't room for clarification/discussion about our design needs - which has been helpful when working remotely from another city (in this case San Francisco).
It would be great if you could see examples of other people who have used your services prior but once again that goes back more towards making sure everything runs smoothly after payment etc..