On Fri, 23 Feb 2018 22:42:47 -0500, "Tom Del Rosso"
wrote:

I just twisted a torx bit into a spiral trying to remove a rusted screw,
then used a Dremel to cut a slot across the top and took it out with a
flat screwdriver. The screwdriver didn't bend at all.

None of the bits I ever saw are made of hardened steel like a
single-piece screwdriver. Does anybody make harder bits?

Try Milwaukee bits. There are a number of others that are designed
for impact drivers but Milwaukee are the best, IMO.