I like most of what I see about this product but that is an easy one to answer! Nothing really. This product seems pretty good for its price point. It's not as intuitive or user friendly as some other products out there. We are able to use it with our C# programs without too much trouble (although we do have to learn how to work with the SQL syntax). If you're looking into something relatively inexpensive where your code can run off of it easily then maybe take the plunge into this product. You'll be happy once you get used to working with it. We've been using it since 2008 so we know all of the ins and outs now.