154cm vs. 440c in terms of corrosion resistance has been an ongoing and long winded debate... Many claim 154cm is notably better; others (myself included) were under the impression that in achieving better qualities elsewhere, the trade off was (slightly) less corrosion resistance... (Some have even argued 440c's edge holding as still being sufficient to 154cm).
I can only surmise that the two are actually really close on terms of corrosion resistance, and very well may overlap depending on whether the 440c contains just 16% chromium or the upper limits of 18% (as well as whether it contains just 0.95% carbon or 1.2% carbon compared to 154cm's 1.05); with thresholds that wide, you can have a <1% carbon and 16% chromium 440c that would be far less corrosion resistant and far less edge holding as a 1.2% carbon and 18% chromium 440c, both still legitimately within the parameters of being called 440c.
154cm only has 14% chromium but with a small bit of tungsten, vanadium, and 4% molybednum (compared to 440c's 0.75%) equaling 18.8% total in those alloying elements.
So then in theory, if you have an 18% chromium 440c plus that 0.75% moly equals 18.75%, and you give it 0.15% more carbon, and consider 1% maganese for 440c vs 0.5% for 154cm, everything else being equal, in that scenario 440c would have slighlty less overall iron content with a significantly higher 4% chromium content, and very well could be better at resisting rust then 154cm? If it was 16% chromium, as well as lower carbon, you'd then have quite a bit more iron content then 154cm (which iron is what rusts) and just slighlty more chromium, and thus it very well could perform significantly worse then 154cm regarding rust resistance...
So what recipe for 440c was used in the blade you got could be the deciding factor? Whatever the case, I image benchmade would have used a good mix of 440c, so if there is a difference either or, I think it would be minimal at best, both are still pretty rust resistant.
