Can only agree with all the advocates for gauge plate, hardened or otherwise.
My experience of magnet retained Aluminium soft jaws is that they don't stay retained for very long. Then I hammered over the top and ends to retain them. They stay in place when gripping, but fall off as soon as the jaws are opened. NOT good for blood pressure or temper, but keeps the back supple picking the…………things off the floor or bench!
Fibre jaws don't grip as well, and soon get mangled. I have a new boxed set on the shelf that I can never bring myself to use, for that reason!
Howard