I have a nice, vintage Centurion with Sugino cranks, bar end shifters and SunTour cyclone GT front and rear deraileurs and was floating around on EbAY and come to find that this stuff is valueable! My question is, why? What makes, what looks to be garage sale fodder, valuable? The stuff is in great shape and has almost no miles on it as can be seen by the wear and tear to the various parts. Still, desireable? Why?