30 ft is a good length. that way when you are yanking on someone the vehicle doing the pulling is far enough away that there will not be a collision when the stuck vehicle becomes free. and you can get a better running start along with being on slightly different terrain, like out of the mud hole.
you can double it back for flat towing someone out of the trail.
I have broken a 2" and a 3". I don't know the weight ratings off the top of my head. I have a 4" that I bought for about $60 years ago. one end has a little bit of fray but that is from improper use. I keep it dry and clean, that helps a lot in preserving a strap.