Dave:
The sum total of my knowledge about these guns falls squarely between nothing and zero. I bought mine many years ago, based on consulting with members of this board, principally, as I remember with Jerry Lape. I really like it although it was choked extra full and "slug". He said that was typical. Sold it to a waterfowler. As I recall, the comparisons were made with the more current Model 60's and Royal. It was definitely a higher grade than the 60 and equal to or better than the Royal, except for the scalloped frame.
It looks like what you found on the net was an excerpt from Shooter's Bible. My copies of this (1959 and 1960) will be going to Ellenbr. They are a bit more detailed. I will copy a couple of the pages and post them here in the next few days.
Sorry, not much help!
Roy