Interestingly, I brought the roadbed to the local hobby store, since I wanted it to be preserved if the roadbed could be useful to an AF aficionado The first question asked, was, "Do you have any straights?" When I said no, he indicated that the only reason he bought curves from someon was to get the straight sections of the roadbed. He has plenty of curved sections.
I laughed to myself, now understanding why a hobby shop that was closing had only 53 sections of curved roadbed!!!
Having been in business since the early 1980's, the hobby store owner was also familiar with the older, 3-rail AF track with the nail-like pins -- obviously an antiquated design, but probably very effective in holding the track together for "floor" layouts.