The dm 500 ( now only sold as clone ) is a good beginner box , but you MUST be aware off clone killer images !.
The 500+ is the cheapest genue dreambox on the market .
The 70xx series offer ci slots for cams and usb / cf ( this is considered as the real dreamboxes )
For HD only the 800 is availble NOW , but the 8000 will be released soon .