The ease of use, the ability to put in multiple numbers for different campaigns/brands, and the powerful reporting features that are available when using this software. Nothing really! I like that it is easy to set up and use at an enterprise level. The customer service can be hit or miss. Sometimes they're great and sometimes they don't have answers for you. This is one of those businesses where if you want to do business with them, they'll come through. You will need to run reports on your own with their software. They provide very limited support, so you'll have to figure out how to get what you need done yourself. For our needs, we needed to run reports and keep track of phone calls made by our sales teams to various companies/customers. It was able to pull all that information together.