Wow...this is an old thread. I got that replacement, and it's a good camera. I got another chrome LTL from a friend just for shipping, and I used all of the black parts from the broken LTL on the extra chrome one.
That was very much the point, the Russian were only used as training, so as not to ruin the expensive Leitz items. Same layout and principles, and if you could master adjusting and servicing the Russian cloth shutter, then you were considered safe on other items. Only after several years were new technicians put on modern Leitz, or rare models. The horror shutter was the Contax, with bent blinds or twisted runners, again you were given a Kiev to practice on, the core parts are the same.
Some customers specified only Leitz trained technicians were to service the equipment anyway, the owner was, and he had designed cameras, there were none that caused any problems, bar vintage of a date when spares had to be made. The only one he reserved to do was the Bell and Howell Photon shutter and clockwork drive, and he providing help to others with Periflex, which could be very awkward to work on.
Most Leica clones of any engineering standard were easy, the Canon was serviceable as was the Yashica and Leotax. Others were frankly poorer to work with, but always worked in the end.
A well adjusted Russian shutter worked fine, but the noise level was so much higher than the Leitz, a thump and bang shutter compared to the near silent Leica. Stephen.
"...as the plastic gear ages and warps, leaving a very sick mirror return."
The plastic gear in my LLC broke at some stage in the 1970s. I reshaped it, make a plater cast and made a replacement using acrylic. The repair is still working. I did think of making a replacement in cast metal, but the acrylic one was too successful, so I never bothered.