As has been stated in other ways above, the issue is cost/benefit.

The rotors are by far the most expensive part of a twin screw. Until the recent rise of CAD/CAM, they were prohibitively expensive to machine. Best case scenario is that a couple of thousand get sold. At those production levels, the cost of the rotors would likely be more than a KB or Whipple.

And you would still have the limitations of the Eaton case to deal with.