i'm not that intimate with 154cm. i just got my first two samples when i got the mple and the zt0200, so i can't really comment on retention. i can tell you that 12c27 can attain a much thinner edge without fracturing than the powder metallurgy steels i'm familiar with. if 154cm is no exception, then edges are kept thicker deliberately to prevent damage. you can put a thick edge on 12c27 and it'll hold it just as well.