I've got these on my 928. I replace them every year as a safety measure.

They don't improve braking performance. They do improve brake pedal feel
a lot. Really firm and if it's not then there's somehting wrong. Nice to
know at the track.

I don't think they do.  However, the feel does improve dramatically and
if nothing else they are cheaper than a set of stock rubber lines so you
might as well do it.  (at least they were cheaper on my 944.)

Take your time when working the lines loose, unless you like breaking
stuff.  The old fittings are likely fairly tight and won't come free
without some penetrating oil and maybe even a little heat (as a last
resort.)  Don't even try to do this without flare wrenches, and if a
fitting feels tight, clamp some vice grips on your flare wrenches to
keep them from spreading open.

good luck,

nate

From what I remember the braded line was intended for use with real
race cars that were running silicone based brake fluid which required
higher line pressures.  Thus the stainless steel brake web to prevent a
blowout!

A Google search for > "braided brake line" +reason < resulted in the
following at: http://www.mitsubishi-fto.org/workshop/brake_lines/

This article even answers the question about, "why never use old brake
fluid."
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"What are the different types of brake fluid?

The three main types of brake fluid now available are DOT3, DOT4 and
DOT5. DOT3 and DOT4 are glycol-based fluids, and DOT5 is silicon-based.
The main difference is that DOT3 and DOT4 absorb water, while DOT5 doesn't.

One of the important characteristics of brake fluid is its boiling
point. Hydraulic systems rely on an incompressible fluid to transmit
force. Liquids are generally incompressible while gases are
compressible. If the brake fluid boils (becomes a gas), it will lose
most of its ability to transmit force. This may partially or completely
disable the brakes. To make matters worse, the only time you are likely
to boil your brake fluid is during a period of prolonged braking, such a
drive down a mountain -- certainly not the best time for brake failure!

As a DOT3 or DOT4 brake fluid absorbs water, its boiling point
decreases. It can absorb water from the air, which is why you should
avoid opening your car's brake fluid reservoir. For the same reason, you
should always keep containers of brake fluid tightly sealed.

DOT5 fluid does not absorb water. This means the boiling point will
remain relatively stable, but it also means that any water that does get
into your brake system will tend to form pure water pockets, which could
cause brake corrosion.

Two other important things about brake fluid: DOT3 and DOT4 eat paint,
so don't spill it on your car. Also, none of the different types of
brake fluid should be mixed. They can react badly with each other and
corrode your brake system. "
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