This article is from the VW Performance FAQ, by with numerous contributions by Jan Vandenbrande others.
A:The reports I have received is that it improves brake
feel marginally (less expansion of the tubes) but that
the steel is also subject to more corrosion.
[According to Volney.Spalding@Corp.Sun.COM]: They are not
recommended for street use. Reason: Lines are rigid and
will not flex with the body as it turns and reacts to
road imperfections--rubber hoses will. As a result, the
lines can often get pinched and fail. Stainless lines are
OK in racing applications because race cars are subject
to constant inspections/bleeding/maintenance. If there is
an alignment problem it will likely be discovered. Most
people probably are not as disciplined in street
applications making the this mod impractical. In
addition, most steel braided brake lines do not pass the
DOT tests and therefore technically illegal for street
use.
 
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