Some Herter's dies were OK, others were not.  I don't think you can generalize.  They may have been rejects or low-end contract stuff from some other company.  I don't think Herter's made anything except fiberglass boats & such themselves.  Everything else was made elsewhere and George Leonard Herter put his name on it.  My Dad called him George Leonard Hotair.

I have Herter's dies in .30-06 that are OK and a set of 6.5 Jap that are so badly off that I have used them when making .220 Swift into 6mm Lee Navy.