Just my 2 cents worth....

I'm a former camera tech, and have owned quite a few cameras over the years....What I've found is that pro's serviced their gear on a regular basis - they understood how they were earning their $$$

Most amateurs only service their gear when it's broken.....

Back in the 90's I bought a heap of gear from a major newspaper that was changing from Canon to Nikon...I got something like 50 odd lenses and 20 bodies....out of all that I got maybe 1 faulty body, and a coulpe of lenses that needed repair - but these were freebies that were "thrown in" with the gear I bought..I sold off what I didn't need, and used the rest....

I used 2 of the bodies for nearly 8 years shooting motorsport in all sorts of weather - I can remember coming home from a race, and having to dry the cameras out as the seals were saturated with water (from being used..and they were under rain hoods!)...not a problem......

Then again after shooting a off road event I had to strip one of the lenses, as that much dust got into it that the focus ring was starting to stick in places, but the cameras were fine.....

Services what was needed when it was needed....

I sold all my NF1 gear when I went AF.....

I got nostalgic a couple of years ago and bought one of hte cleanest New F1's I've seen in years..only had amateur use - even has that dull black sheen NF1's had when they were new...looks georgeous..

It also doesn't focus to infinity correctly - the flange depth is out....but the previous owner never knew....just thought their eyes weren't as good as they used to be....