DETAILS, FICTION AND AUDEMARS PIGUET

Both equally should work. You will likely really need to sharpen extra regularly with HSS. But, I manufactured a couple of dozen blanks for bezels outside of 40mm bar, turning operate was with carbide, but made use of HSS for parting off, and obtained all 12 parted without the need of sharpening the Reduce off blade, and had to touch up my carbide