I have some Torx and Security Torx bits from Wiha, and they are very high quality. I've used them on my modified step slider project (96 Torx or Security Torx fasteners), which I installed and removed probably five times during that project. I started with other brands of bits and they gradually twisted. They still worked, but there was a noticeable helix angle that developed. In contrast, the Wiha stayed straight as a rail. I generally use impact for loosening and hand tools for tightening (I like to feel for yielding.) The impact loosening didn't seem to twist the cheap bits - probably because it's only a few hammer impacts and they are pretty loose. They only twisted when tightening by hand, and I didn't tighten any with impact.
And, as a crazy coincidence, this just showed up in my email today. Apparently it's National Tradesperson Day (it's hyperlinked):
View attachment 643996
No, I don't work for Wiha - just passing on a good deal.