The old Kreg screws that most, if not all, of the 5 star review are for are not the screws you receive when order the new ones.  I recently finished off my last box of 1,000 screws I had ordered several years ago.  These new zinc-plated screws do not self thread nearly as easily and the square drive does not nearly as securely.  I am very disappointed to see the steep drop-off in quality.