Well.. I dunno much about knives from that steel, I do can tell you what the steel is and why it is not common found in blades.
M3 is a higher carbon version of M2, used in for example the Benchmades HSS blades. It has .10 % carbon more, so there isn't much of a difference, you could say it's hi-quality M2 or HSS.
Now M3 or HSS is designed for cutting tools like drills and taps, which can whitstand heat very well while keeping their edgeholding.
I've made some knives from HSS, and they do hold their edge, but they aren't as tough as I would like them to be. Maybe it's because this is a high alloy steel, and very complex composition, that the Heat-treath was a little off, but i doubt that.
Personaly I prefer 5160 or 52100 or 0-1 over HSS anyday, simply because they are tougher and have a better tuned HT, and easier to perform HT. They become tougher and better edgeholders if HT'ed correctly.
The whole HSS and M - series aren't used much in current knifemaking because the ability to hold an edge at hi temperatures is not important for knives, and the alloys were specifically made for that purpose. In this context you could say the other carbon steel alloys used by knifemakers are better then HSS in almost every aspect.
HSS is also used in stanley knives and hobby scalpels because the stuff hold a great fine edge and is easy to work in mass. It's also moderately stain resistant. Other steels such as D-2 or 52100 would have been better edgeholders but are tougher to come by in the right sizes and tougher to work dont to small sizes.
hope I helped you out a bit,
Greetz and take care, bart.