You do what you like on the
oil line. I have put a lot of miles on my car and had no problems whatsoever with nylon. I've also used it in muscle cars and off road racing applications with no problems. Part of success is putting the line out of harm's way. If it's too long and you have extra coils looped around, shorten it. There's no reason for it to ever get near anything hot enough to melt it. SuperHart is right about copper. The more you bend it or vibrate it, the harder it gets. Use the trick line if you like. If nothing else, it may give you peace of mind. I've just never seen the need for it. I do use aircraft lines for my
oil cooler, so I'm not against it, just don't see the need to spend the money.