From Epson's site
EFI® eXpress for Epson included with Designer Edition Bundles
•Easy-to-Use intuitive interface saves time and produces accurate output.
•Print directly from the latest creative design software, or drag-and-drop files to a hot folder.
•True Adobe® PDF and Postscript 3 print engine ensures compatibility with your design files.
•Professional ICC color management, based on BestColor technology used in the commercial EFI Colorproof XF RIP offered with the Epson Proofing Edition Series.
•Handles both CMYK data for accurate proofing to industry standards, and RGB data for exceptional results with Photography and Fine Art.
•Reproduces accurate spot colors with the included PANTONE, DIC, HKS, and TOYO libraries.
•True cross platform network printing via hot folder or eXpress Virtual Print technology.
•Software supported on both Macintosh OS X and Microsoft Windows operating systems.
•Includes Epson media support out of the box, and the ability to add custom media types.