According to the manufacture, copper nickel brake lines are the best thing since sliced bread. But they seem too good to be true, they bend easy, won't rust, are DOT approved, flare easily, and can be polished to a stainless like shine. And the price isn't that bad. Anybody using them?
I just replaced mine with copper nickel. I chose copper nickel over pure copper, which is common here in Europe, mainly because I think it looks better (more like factory lines).
Flaring was not a success with the simple tool I used initially, similar to this one: Flaring tool
It put on a flare without a problem, but it was hard to get it properly centered. I've used this tool before without a problem, but at that time I was using regular copper lines, which are softer. After getting tired of making flares that weren't good (enough), I bought a more professional flaring tool for about $150 which makes nice flares if you prepare the line properly.
The lines bend easily, but since they came in 15ft rolls, it was hard to bend them back into straight ends so the end result is not so professionally looking after all
Since I just put on the last one on Saturday, I can't common on how well they hold up in the long term.