PostgreSQL or HSQL for the Disk Quota store in Geo Web Cache for production systems

As the title says, I’m looking for feedback on whether it’s recommended to use PostgreSQL or HSQL for the Disk Quota store in Geo Web Cache for production systems.

I see some (e.g Andrea’s comment) recommendations to use PostgreSQL over H2 for older versions (which we were currently on, but were considering upgrading), but not for newer ones.

So the worry is we will waste time upgrading to PostgreSQL only to find out HSQL is better or as good.

Please ask me any questions if something is unclear and thanks in advance.