There is more than one type of Dye Sublimation Inks.

the Ricoh/Virtuoso printers use 'Subli Gel' inks, where as other printers use Dye Sub inks (water based). This is the reason Sawgrass printers do not require as much maintenance to prevent the inks drying up. This is also achieve with the larger print heads in the Ricoh/Virtuoso printers to handle the Gel based inks.

Also Subli Gel inks have higher UV resistant rating, than dye sub inks. *However I'm still trying to find the source of evidence for this.
Sawgrass does make mention of the UV improvements, but no direct comparison with dye sub inks.

SAWGRASS product user group
Facebook independent User group

Sawgrass own youtube Chanel.