The ability for me as an individual user, or even with my team at large (including non-technical) users is extremely simple in terms of getting started quickly but also allows us to drill down into our metrics without having technical knowledge about how it works internally! While there are many tools out their that do similar things - I have not found anything else quite like this one yet from them.
It would be nice if they had more robust reporting capabilities beyond just dashboards though. We use compellons primarily through Salesforce Data Studio so we can pull all kinds of insights directly back up into SFDC via SSJS/API calls.