These are very different product offerings. Power BI offers a mature in-memory columnstore database with a custom functional query language, DAX, with full dime

These are very different product offerings. Power BI offers a mature in-memory columnstore database with a custom functional query language, DAX, with full dimensional modelling facilities. Additionally, if taking advantage of the (freemium) Power BI web portal, you get natural language query and cross-platform mobile apps. This is essentially a SQL query builder on top of a RDBMS with some nice visualizations. I am not trying to disparage the project - in fact I'm often of the opinion that a good query builder is all most organizations need for BI, but the two products in question are vastly different. Power BI has tooling to perform ETL, data modelling, and reporting. Metabase only covers the last piece. In terms of performance, Metabase, being on top of a SQL RDBMS will have the potential to be incredibly speedy, but with large data volumes, you will need a DBA to make sure reporting scales appropriately. With Power BI, that conversation comes much later in the game. 10Ms of rows are trivial with a star schema and sufficient RAM in terms of performance tuning. With a SQL solution, there is a lot more back-end work to tune for an ad-hoc BI workload even at the 1Ms of rows level.