I always replace everything from pedal to pads on anything questionable, or has been sitting for an unknown length of time.
Still finding everything over the counter.
That's the part that surprised me.
These systems are so easy I can do it in an afternoon or two.
I am no pro by a long shot.
No fancy lines and only a bender and flare kit for "special" tools.

These systems have lasted 40 years once and will do it again.
By then I will be long gone.