The article is about both 420j2, which is indeed cr@p (as is 420). These are the 0.1% to 0.15% carbon steels, which just barely get hard (Rc50-53) enough to be considered knife blades.
They also write about 425Modified, which is very nearly the same as 420Mod and 420HC (Buck's fav). The key is the carbon level, which ranges between 0.4% and 0.54%. These steels all make mediocre blades, as they top out around Rc56-57, depending on how much carbon, who heat treats and how, etc. These steels are in the range of AUS-6, basic entry level stuff, brought to market in the $15 to $30 range. If you are going to buy a cheap knife, I'd be tempted to trust Buck before most others... at least they have Paul Bos on staff.
AUS-8 is a small but notable step upward, mostly because it has 0.7-0.75% carbon and gets harder.
For these simple, basic stainless steels, hardness is all you have working for you, assuming they didn't foul up the heat treat and fail to temper them properly (so they aren't brittle).
The 420/425 series stuff can be fine blanked, makes production cheaper. The 440 series stuff can't be as easily blanked, and is more expensive to purchase, and apparently becoming more difficult to acquire in the marketplace for some reason. 440A, 440B, and 440C are only superior to the 420 stuff because they have increasingly higher levels of carbon, and can be run harder. 440's have more chrome, but it doesn't help corrosion resistance much vs. 420 (in fact, 420 tends to be more corrosion resistant than 440C), and in fact makes the 440's a bit more brittle.
Whether Cold Steel cryo's or not, well, it can't hurt if they do a temper before cryo, it might help convert some retained austenite to martensite, but the fact is they are using it as a marketing tool, and if they are doing cryo well, at best they are optimizing a cheap steel, at worst they are inducing stresses and spending more on heat treat of a cheap steel. Which is fine if they bring these to market at an affordable price (like Buck does).
Caveat Emptor.
It is funny to catch Lynn having to eat crow though.
And don't let anyone tell you that 420HC, 420Mod, and 425Mod are significantly different. 425Mod has a bit more chrome, another 1.0% or so, and that's most of the story.
All of the 420's are very corrosion resistant, their primary benefit (aside from being cheap).
See Spyderco's steel matrix for the compositions if you are interested:
http://www.spyderco.com/education/s...7+PM&mscssid=KT8WBVS1F2DX9JQEM35TH1RV0422DXFC