How is your project coming?
I'm surprised you are using ball screws and a control without backlash compensation. Do you just need fast, without concern for precision? Is there something else drawing you to duet?
If duet had backlash comp, I'd put it on one (or more) of my desktop machines, but without it, I'm sticking with the existing LinuxCNC. I suppose one could use a Marlin or Beagle board, but I haven't used either yet, so I don't have a favorite or a reason to migrate. (Like standardization.)