Just got a microtech combat troodon today that has m390 steel. I don’t know much about different steels but the google consensus is that m390 is pretty dang good. I’ve never really heard of it until recently. I’m used to hearing about d2 and the CP steels. I’m guessing the main difference in the steels used for the better quality knives like microtech, benchmade, kershaw etc. is some are softer but easier to sharpen and others are harder and retain edge better but harder to sharpen? Always been kinda curious about different steel types as I’ve had a lot of knives but was just a casual buyer who didn’t really know what I was getting in terms of steel.