The Dreambox is a digital satellite receiver running on the linux operating system. This means that an operating system (OS) is embedded in the Dreambox. It should be noted that linux a free operating system for everyone (Open Source) and therefore the company Dreambox multimedia, which manufactures the Dreambox, used it to manufacture all these models including the Dreambox 520 HD
The VU+ is a digital satellite receiver running on the linux operating system. This means that an operating system (OS) is embedded in the Dreambox. You should know that linux is a free operating system for everyone (open source) and therefore the company MARUSYS which manufactures the VU +.
Enigma is an operating system of STB (Set Top Box) that runs "on" Linux. It was developed by Dream Multimedia to shoot on DB STBs. Enigma was Open Source which made it a reference for all STB running Linux (VU +, Dreambox, Formulate F1, Azbox ...)
The choice of the image depends on the tastes and colors but also on how the menus and submenus are organized and some features integrated on some images and no others that will please or not, the pictures we recommend are BLACKHOLE, VTI, OpenPLi for IPTV