The #DasKeyboard Professional 6 *product* is fantastic.  The quality control and support are sadly lacking.  Despite being marketed for #Linux, they only release firmware updates for Windows.  The cable connection went bad on my original one and my replacement came in damaged.  The box wasn't damaged.  It appears to have come from the warehouse like this. 😬 

For the top tier price, they really need to step up the support and QC on these.