You wrote, "when you are using an ORM, most of the arguments [against using a different DBMS for testing than production] are obsolete, too," which is false, un

You wrote, "when you are using an ORM, most of the arguments [against using a different DBMS for testing than production] are obsolete, too," which is false, unless the point of the ORM is to bring the production DBMS down to the test DBMS's level of capability.