You seem to consistently be missing the point. The "build quality" on TLRs varies, just as it does (did) for manual SLRs. Some are better than others. The more expensive and "better name" generally means better build quality. But they aren't like Timex watchs. Remember them --"takes a lickin' and still keeps ticken'"? They require periodic maintenance under normal conditions, and repair under harsher conditions. As an example, I bought a Rollei about 25 years ago. It was essentially NIB but it was still 15 - 20 years old. The shutter ran, but indicated that it needed its lubricants refreshed. $100 (1980's dollars!) later I had a NIB Rollei that was performing to factory specs. I used it for 20 years, then retired it -- not because it was broken, or anything else -- but because I needed interchangable lenses so a MF SLR met my needs better.
Originally Posted by h.v.
Re: 35mm SLR... call me foolish, but I had my 1981 Nikon F3 overhauled a couple of years ago "just because" and I'll bet it will run another 20 years if I don't abuse it. The cost for that overhaul was probably twice the price of a "new one" on ebay, but I know it is performing to factory specs and can be counted on to get the job done. That ebay one -- who knows?
I'm glad you enjoyed the links.
p.s. "the fundamentals of photography" includes how to use of hand-held meters.