Compression fittings

Who here uses them? I have used them on damn near every vehicle I've ever owned in the last 20 years and never ever had a issue or fail with them. I was reading an article today saying that you should never ever use them on brakes I have used them on brakes fuel lines etc and like I said never had a problem. What are you guys opinion?

Compression Fitting Union CF 38 Three Eigths.jpg

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