The ability to combine all customer attributes in one place so it's easy to see what you are doing right or wrong as far as marketing strategies go.
I don't have any dislikes about this product but would love if there was more transparency into how they make money from our information since we pay them monthly. We've been able to track everything down to individual customers and their purchase history which has allowed us to create targeted campaigns using various channels such as email, SMS text messaging, Facebook ads, Google Ads (as opposed to traditional display advertising), etc.