Trailer Brake Question

Twist in my exp have been fine on stranded, not sure why other guy objects. The downfall is that the twist is open to the elements, so if outside vehicle then there will be more corrosion possible. I have never seen twist on stranded wire come loose if installed tight. It works wonderfully. There is waterproofing tape that can seal it all up.
The crimp things are only good for very low voltage applications like wall telephones. They are easy to use, but I have seen a lot of issues with them. Often these are the culprit when tracking down issues.