Not my thread, but I chose stainless for my everyday driver / show truck because I know they will last near forever.
The truck I just worked on, replacing all the lines, I used regular steel brake line. It is by far easier to work with than stainless.
The stainless I used for one truck is 3/16", and the steel on the other is 1/4", even though the steel is larger it is easier to bend than the smaller stainless.
Unless you plan to keep the truck forever regular lines will last and last, and much easier to flare and install.
This being said, my next line project is a bunch of 1/4 and 3/8 stainless brake and fuel lines.
Grigg