I'll usually ask such customer to save up a whopper of a job, then I be onsite to see it run. The longest was a Mita DC5585 that ran 5000 without a hitch. He was quite irritated by my suggestion that the proper loading of the paper is quite important. It was hilarious watching the agitated customer turn various colors of red and purple as the machine just ran & ran & ran, and I kept feeding it. He never did call back for that "constantly jamming" again, especially since I could say exactly how many actual jams there had been. =^..^=
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