Signkiosk have since upgraded to the newer Epson SureColor S80660L. Read the article here.

Epson® enters high-end signage market with launch of the Stylus Pro GS6000
New UltraChrome™ GS ink delivers widest colour gamut for indoor and outdoor applications
Epson is launching the Stylus Pro GS6000, a 64″ large format printer with an 8-colour ink set, offering the widest colour gamut to date in a printer designed for both indoor and outdoor applications.