Ok, so seriously I am not ragging on the guy. It was a interesting read. But it confuses me a bit. I consider myself very much a novice still. But I don't agree with the this gentleman.... Basically what he is saying is SK-5 is a better steel and more rust resistant then O1?? Isn't SK5 just a version of 1085, which is still a high carbon steel that rusts? there is no stainless aspect to 1085/SK5 is there? And O1 is a upgraded 1095... from all I read it holds a edge a bit better then even 1095 and is tough as I need a knife to be. I have never had a problem sharpening O1, no S90V... ugh lol So.... how does he reach his conclusion that it is a downgrade? I'm lost. Educate me gurus, am i off? Here is the review he wrote and the link (am i breaking a rule here? hope not) http://twacorbiesbushcraft.wordpress.com/2013/11/18/cold-steels-prestidigitation/ "I thought fellow fans of bushcraft knives might be curious about this news: Currently, some of Cold Steels most popular knives (the Trail Master and the Recon Scout) are made of SK5 which they are planning to switch to O1. As I noted in my review of the Trail Master, SK5 is an excellent steel of moderate hardness and good rust resistance. Such a big knife needs a more forgiving, less brittle steel. SK5 is hard enough to take and hold a good edge, but it grinds easily for sharpening, and it is just springy enough to be used as a chopper without chipping the edge or breaking the blade. Below is a note on SK5 steel from knifesupply.com: SK-5 : A high carbon steel made in Japan. It is the Japanese equivalent of 1080. It has a high hardenability. It has a mixture of carbon-rich martensite and small un-dissolved carbides. The carbides increase wear resistance. This helps to create a good balance between toughness and edge retention. This steel is often used for making hand tools. Cold Steel is now switching these knives to O1 and billing it as a superior steel. Sadly, in the last few years Cold Steel has been downgrading some steels (no one knows why, except maybe to increase profit margins). The worst case of this was the Leatherneck, a once excellent version of the Ka-bar USMC knife which, when made from SK5, was excellent. Cold Steel ruined the Leatherneck when they changed the steel to cheap 4116 stainless, an unimpressive metal often used to make nail clippers. Now, O1 is not a bad metal, but it is not exactly the superior metal Cold Steel bills it as. Here is knifesupply.coms description of it: O-1 : An [sic] good oil hardening, cold worked tool steel. It has excellent edge retention and toughness. But it is hard to grind and has very low corrosion resistance. It is popular among forgers because it is very forgiving and can be heat treated repeatedly if a mistake is made. After doing a fair bit of research, I am left with the impression that O1 is too hard a steel to be good for a large knife like the Trail Master and Recon Scout. Reports state that the edge may take small chips and that it is quite hard to sharpen. Also that it is very prone to rusting. I suspect Cold Steels real reasons for the switch have nothing to do with superior quality, but that it is easier to get in the USA and more flexible to work with. I really liked Cold Steel once. Its too bad theyve been making the moves they have in the last couple years under new management. They are slowly alienating many of their once devoted aficionados. For my part, Im glad I bought two Trail Masters before the big change to O1. I feel a more resilient, rust-resistant steel has far more bushcraft application than O-1. I would even consider O-1 a downgrade for a smaller knife given its proneness to rusting unless one resides in an arid region such as the American desert southwest."