I like that it has an easy way of showing my customers what they are buying by using their names rather than numbers or codes which can be difficult when you have so many products in your store! It also helps with keeping track of orders/deliveries etc all at once too instead of multiple spreadsheets (which would make me physically ill).
Not much really - if anything just do more research before purchasing such as read reviews from other people who've used this system first hand i guess? As mentioned above though its great being able to show customer's purchases via there actual fullnames not random number code things :D.