How this compares, including when it loses
Every page here names the case where the other tool is the better answer. A comparison that never concedes anything is an advertisement, and readers can tell.
ReportsHQ compared with Metabase
Metabase is a service you run beside your application, with its own login and its own connection into production. This is a package inside it, reading the models you already have.
ReportsHQ compared with Looker Studio
Looker Studio draws dashboards over connectors you configure. This runs inside the application instead, so there is no connector, no copy of the data and no second place for it to live.
ReportsHQ compared with building it yourself
A table, a cron job and a chart library is a weekend. The second year of it is not. An honest account of what you would end up maintaining.