I have a Spotmatic, a Spotmatic II and a Spotmatic F. The II works but could use new seals/foam. The Spotmatic looks like it needs new curtains. The F needs unjamming. The F, like Mamiya's SX series, was an oddball. By the time they came out, bayonet mount cameras with full aperture metering had been around for a long time. The F, ES and ESII were all capable cameras but most people no longer wanted to screw in their lenses. Asahi then brought out their K mount cameras which at long last had the bayonet mount and full apertute metering but had feature sets which were nothing special. They were also somewhat large and heavy compared to the smaller SLRs from Fujica and Olympus. The smaller M series was more attractive but I question how much was really saved by leaving off manual shutter speed control from the original ME. I would rather pay a more modest price for a camera which is not in perfect shape and then get it serviced than pay more for one which I can't really be sure is in good condition other than cosmetically. All of these are old cameras and most of them suffer more from time and lack of use than from overuse. My Spotmatic F regret is that when I saw one with a grid screen I didn't buy it. I have grid screens for all of my cameras with interchangeable screens and have had custom installations done for some cameras which do not have interchangeable ones. My favorite AOC lenses? The 55/1.8 and 55/2 standard lenses in M42 and K mounts.