OK, I know I have been here awhile and I should know better, but, well I don't

Question #1. I have had the 'tour a little over 3 years and never changed the brake fluid. I don't take the car to the track and it's just my daily driver. Most of the 20k a year I put on it is highway miles. But, if better fluid will help prevent fade or something, I'll do that.
Question #2, besides costing money. Do stainless brake lines do anything besides improve pedal feel?
Thanks guys

-Pete