I just acquired a set of the original separate lessons in the red collector's binder, and I have to say the quality of the photos knocked me out. I had no idea how good the original photos were, having never known anything but the Tannen's reprint.
One thing was irksome, whoever owned this set originally bound it wrong. In series 1, lessons 1 and 3 were issued as tri-fold pamphlets. Instead of folding in the right-hand third, they bound it in and split the pages on the fold, which put the photos out of order, and in the case of the first lesson, actually cut 3 photos in half (If you look at the photos in the Tannen reprint of Series 1, lesson 1, you will see a white line through photos 4, 9, and 14) Luckily, I was able to repair the damage.
At first I thought the set was incomplete, as it did not include Vernon's "Royal Monte" or Slydini's "Art of using the Lap as a Servante", but those two lessons, as it turns out, were never issued separately, they first appeared in the bound version.