Stainless steel braided line

Steel brake lines rot out pretty quick up this way with winter salt. They don't allow it in NH. I'm sure steel will be great in your area. I've been using nickle copper for quite some time now with no issues.
I'm in Michigan. Lots of salt and other **** on the roads. Most of the lines become problematic after about 20 years. I've done some stainless lines on customer cars, but you want to talk about a ***** to flare these are tough, but you don't need to double flare them. Does NH require nicop to be used?