My brakes are typical soft pedal feel. I have seen posts of purchasing and installing stainless steel brake lines, but, are they really worth it? Is there marginal improvement? Enough for steep descents down trails?? I would like to know.

 

You'll get better pedal feel, but there won't actually be much braking improvement from the lines themselves. You'd most likely get more improvement from just flushing and bleeding the brake lines with fresh fluid.