I know it's a lot of work, but anyone whose business is dependant on database performance needs to know how the system will perform with their data and their use cases. I think they would also like to put some effort into working with the database to see how well the associated tools work. It would be nice to have synthetic benchmarks to review as a starting point and I suppose those exist for the open source engines such as Postgres, Maria and MySQL. It should be safe to assume that Oracle and MS-SQL are at least as fast and a little testing should verify that.