Is it possible to order an Aurender music server with a Solid State Drive used as the primary storage drive, instead of the included Hard Disk Drive?

No, as Aurender does not custom configure products. This would circumvent our standard manufacturing process and make the product more expensive.

Further, Aurender music servers are designed in such a way that for the majority of end users, the disk used for the main repository is rarely accessed (since the content is cached to the playback SSD when queued, then the hard disk is spun down).  Therefore, any benefit to using a solid state drive as the main storage disk is largely circumvented by the hardware and software architecture.