I've heard alot of things from alot of people. Stainless steel won't rust, and is much harder, but doesn't hold as good of an edge. Carbon steel is flexible for use in longer knives and swords, can hold a better edge, but can't take as much of a beating. I think I side with a good 440 C Stainless Steel blade, but that's just me. What do you think?

High carbon steel such as D2 is heatreated to similar temps as the newer stainless such as 154 CM or SV30 ...60-61 HRC. I've used 440C for years and it's optimum HRC(rockwell is 58-59) Sometimes the edge holding capability translates into how easily it is sharpened. My choice now is 154CM stainless.
Here is a summary published by Midway USA that's pretty good
https://www.midwayusa.com/content/HowToGuides/knife_steel_and_handle_material_chart.htm

I don't know what many of these guys know. But I've carried carbon, and stainless of many different grades for years. Carbon was easier to sharpen, but lost an edge sooner. Stainless is more difficult to sharpen but holds an edge longer. The Case XX I used to carry took a while to get an edge, but held way longer than the Moore Maker.

Now I carry a Benchmade with 154 CM stainless and it has been the best blade I've ever used. I'm thinking of buying some bar stock of 154 CM to make full tang knives out of, I like it so much.

I have always liked high carbon blades because they take a great edge, hold it well, and touch up quick. But like Jason, I started carrying a Benchmade in 154CM and it is damn near perfect! I am tough on knives and this thing just keeps cutting. It strikes a really good balance between taking and edge and keeping it. I have had steels that were a real bear to get sharp but held it really well, but they did not taking touching up in the field all that well. The 154CM holds a great edge and a couple of honing licks from time to time will keep it going and going.

I seem to remember that optimal heat treat on 154cm was a little more involved, but it has been a while since I looked into it. Would be worth the effort for a good skinner though!

-ww

154CM is good steel but in my opinion CPM154 is somewhat better. One of the advantages of CPM154 over 154CM (and cpm steels over mill run in general) is very fine and evenly distributed carbides.
If I remember right, both 154cm and ats-34 have had histories of inclusions and/or impurities at one time or another.
The CPM steels are more expensive but well worth it.

Just a little comment; some cutom knife makers using CPM154 will still refer to it as CM154 out of habit. When I had my knife made, I was quoted the cost on my knife, with CM154 or or S30V. When I asked about CPM154 I found out that, he only used CPM154, but refered to it as CM154 out of habit.

ATS34 was designed for jet engine rotor fan blades, was then modified to 154CM then was reformulated by Crucible Steel to CPM154 CPM stands for Crucibles Particulate Metallurgy.

On D2 Goddard said it takes a sh**** edge and holds it forever!!

On the issue of carbon steel and on the stainless steels the heat treat is crucial to the edge performance. You could have five knives made by diff makers and get five diff edge retentions on the same steel. If heat treated properly a good knife steel can cut a bolt in two with a hammer and still shave!

Definitely this, IMO. I personally like 154CM, either the regular or CPM version, for stainless, and 1080/1084 for carbon, with an occasional D2 or AEBL thrown in. In general, I find the carbon steels take a keener edge and sharpen a little easier, but don't quite hold as long, whereas the 154 is harder to sharpen but will hold the edge longer, with both of them at the same hardness.

FWIW, many of the "stainless" production knives are 440B or 420, cheaper steels that barely harden enough to use. These are not in the same category as any of the modern cutlery stainless steels in use by custom makers.

Carbon steels, i like the way they wear and age.

What, no VG-10 stainless fans?

Those are my favorites as well as ats34

Interesting information. I'm not a knowledgeable guy when it comes to knife steel, but I do know what I like when it comes to woodworking steel. The latest thing, metalwise, that I have now is a new powdered metal (PM-V11) that's available in chisels and handplane irons. It holds an edge way better than anything else I've seen and is actually easier to sharpen than A-2. I wonder if it could make its way to knives, but maybe knife steels need different performance parameters.

I did buy a Benchmade pocket knife (after listening to some of you guys) and was very impressed with its edge holding ability. Better than anything else I've had.