Most gunsmith supply companies sell gunsmithing screwdrivers that are magnetic with interchangeable bits. Fine, except I find if I lay one down on my bench, screws or other small parts are dangling from the bit, or worse, just momentarily before dropping to the floor.
I've bought some Husky screwdrivers from Home Depot that I am beginning to like very much. They have interchangable bits that are held in place by a spring loaded ball detent, no magnet. And these bits are hollow ground to begin with, and are easily shaped with a Dremel toll to correct shape and width. And as an extra bonus, Chapman screwdriver bits work with these shanks.