@photopuck Huh. G4U was the one I had good luck with.

Had to order mineral glass to get my scrip filled by them, maybe that meant a different shop did the grinding.

The frames were amazing, though. High copper or brass content in the metal so they turned green and bloomed everywhere the (very thin) plating wore off, threading for screw holes were smoothed in no time flat; fortunately to the same diameter as paperclip wire.