I watched all of the SUPERMAN episodes which contained commentaries. I have to say the enthusiasm of the two men who provide the commentaries (each man does two shows apiece) is ingratiating, but they don't offer much solid information. For example, they don't mention Rhys Williams in "The Unholy Three" even though he was a well respected character actor with some impressive credits like THE CORN IS GREEN and THE BELLS OF ST. MARY'S. Sarah Patten's name was mentioned in "The Haunted Lighthouse," but not that she was tested and almost played Aunt Em in THE WIZARD OF OZ.
I probably watched six or seven episodes total today, and all of them looked good to great (in "The Haunted Lighthouse," it's so sharp and clear you can see shadows on the seascape backdrop) except "The Stolen Costume" which looks worse than any episode of it I ever saw broadcast. You can never convince me Warners didn't have a better print of that episode than the one in this boxed set. It is almost unwatchable with not an inch of any frame not covered in dirt, scratches, and damage. Really abominable quality. Everything else, though, looks so good that it seems churlish to complain too much.