ATS-34 is still the standard steel Trace uses, but as far as I know, knives in other steels (He offered me BG-42, D-2, A-2 and Talonite) are no problem, it might just take him longer to get the materials. The full flat grind on the Spook makes for a more acute wedge shape than the saber grind of the Axis, so cuts are noticably smoother.
Take care,
Tobse !