The traditional steels have a faithful following, for good reason, but in terms of performance I don't see how they can compete with the CPM process steels for strength, toughness and wear resistance--or compete with Stellite 6K for corrosion resistance and edge holding.
Of the CPM and cobalt-based offerings, the blade material I prefer depends on size and intended use. For a 4" or shorter fixed hunter, I like CPM10V for a super thin beveled cutter with maximum strength, aggressive edge, and long edge life. I have both forged and stock 10V blades in this configuration, and haven't been able to tell a big difference. Both at about 63 Rc, and both super workers. For the same size blade that needs to be extra low maintenance, such as in a folder, but still take a super thin edge, S90V (CPM420V) is just right, and if it needs to be a little tougher and still hold an edge forever, I prefer Stellite 6K. My EDC right now is a small carbon-fiber Carson M4 in Stellite 6K, and I'm not looking to change--ever.
For a big, tough knife that can stand up to all manner of abuse and still take and hold a high-performance edge, I don't know which is better--INFI or CPM3V--but I'll happily take either.
I'm really intrigued with the new CPM stainless known as S30V, just now coming into the market, and can't wait to see it tested--not to mention testing it myself. Wonder if someone might have a blade they'd like to see abused in the worst way? I hear there's a guy in Georgia who makes big, strong knives out of the best steels on the planet--maybe he'd send me one.
-w