P.S. box rebuild FirmFeel or Steer & Gear?

I heard someone post that the Firm Feel rebuild was $600. Shipping your core to them could be another $100.
That is less than a Borgeson but not by much.
This really is a matter of “spend a little more and you’ll not regret it”.
Is the Borgeson unit a different design all together? How does it eliminate the dead spot in the middle? Or is it just because the internals are brand new? Do they make a manual box as tight as the power steer unit?