There are lots of good knife steels out there. INFI is truly amazing stuff, though. And it is not too hard to work. It grinds easily yet takes a very sharp edge. It doesn't throw a lot of sparks like S7 and 1095 do. It is expensive. I think a lot of collectors could just get the Busses in 420J2 and be just as happy, since they never sharpen or use them. But I have used and abused them. I can tell you from experience that it is very fine steel. It holds a great edge, yet sharpens easily. And it can take a lot of shock and force, too. It does not rust easily, either.