Although pitman didn't include the RMD in this comparison, I think he would agree that it is one of the best, if not the best, of all the mid-sized knives.I have a drawer full of midsized knives, and the RMD is without a doubt my favorite all-arounder, with the DMDC right behind it. In the 4" size, my SS4 rules. In the 6", it's the S6. Just my opinions based on personal use and experience. I'm sure the Koster is very nice, but I wouldn't give up my RMD for one.