do they have a plastic coating over the stainless?
The problem with many ss lines is that they do not have a cover over the stainless braid. Over time, grit gets in there and wears away at the teflon liner as the line is flexed. This may be your problem.
i bought those ebay lines with the blue anodized fittings, nobody ever buy them i blew one on the first ride (hard break in i guess) and now i have 2 that leak, should have jsut bought the russels (which are now on the way) in the first place, i hate being a cheap bastard
How does the braid look around where the leak is? If the line was kinked at some point in its life, especially after the proof test, it could easily spring a leak. If it was kinked, the braid at that point should not be perfect anymore.
The grit in the braid argument is bogus. I had a set of lines on my Supra for 10 years before I decided to replace them. I replaced them because I also was also replacing the calipers and master cylinder, simply because they were 10 years old. The lines looked just fine. They were basic Earl's lines with no protection. I drive my Supra in rain, snow, sun, all the time! They were filthy.
My best guess is the line was kinked sometime in its life. They're very picky about that.
Are we talking about the same goodridge lines here? I can't kink the ones on my mountain bike with PLIERS. I might be able to with a big set of vice grips, but I rather doubt it would cause any damage.